Mammalian proteins that bind to FKBP12 in a rapamycin-dependent fashion

ABSTRACT

A protein complex containing 245 kDa and 35 kDa components, designated RAFT1 and RAFT2 (for Rapamycin And FKBP12 Target) interacts with FKBP12 in a rapamycin-dependent manner. This interaction has the pharmacological characteristics expected from the observed in vivo effects of rapamycin: it occurs at low nanomolar concentrations of rapamycin and is competed by excess FK506. Sequences (330 amino acids total) of tryptic peptides derived from the affinity purified 245 kDa RAFT1 reveals striking homologies to the predicted products of the yeast TOR genes, which were originally identified by mutations that confer rapamycin resistance in yeast. A RAFT1 cDNA was obtained and found to encode a 289 kDa protein (2550 amino acids) that is 43% and 39% identical to TOR2 and TOR1, respectively.

This invention was made with government support under MH18501, DA00266, and DA00074, awarded by the National Institutes of Health. The government has certain rights in this invention.

BACKGROUND OF THE INVENTION

The natural products cyclosporin A, FK506, and rapamycin are potent immunosuppressants with realized or potential clinical applications in the prevention of graft rejection after organ transplantation and the treatment of autoimmune disorders (Borel, 1986; Kino et al., 1987; Martel et al., 1977). These drugs act by inhibiting intermediate steps in the signaling pathways that effect the T-cell response to antigen (for reviews see, Fruman et al., 1994; Kunz and Hall, 1993; Liu, 1993; Schreiber, 1991). This makes them useful probes for identifying the components of those pathways and determining their physiological roles.

The immunosuppressants interact with the immunophilins, which are small, soluble, receptor proteins that mediate their actions. Cyclosporin A (a cyclical undecapeptide) binds to cyclophilin A, whereas FK506 and rapamycin (two related macrolide antibiotics) bind to a distinct receptor protein, FKBP12 (Handschumacher et al., 1984; Harding et al., 1989; Siekierka et al., 1989). Though cyclophilin and FKBP12 differ markedly in amino acid sequence, both immunophilins have peplidyl-prolyl cis-trans isomerization (rotamase) activity, which is inhibited by their respective ligands (for review, see Heitman et al., 1992). However, this inhibition does not appear to explain the effects of the immunosuppressants (Bierer et al., 1990a, b; Tropschug et al., 1989). Instead, the action of cyclosporin A and FK506 derives from the binding of the drug-receptor complexes to the calcium-activated protein phosphatase, calcineurin (Liu et al., 1991). This association inhibits the catalytic activity of the phosphatase, which is required for the Ca⁺⁺-dependent initial step in the activation of the T-lymphocyte via the T-cell receptor (Flanagan et al., 1991; Kronke et al., 1984).

On the other hand, rapamycin appears to block a later, Ca⁺⁺-independent stage in the T-cell response. This drug selectively inhibits the IL-2 stimulated G1 to S cell-cycle transition that initiates T-cell proliferation (Dumont et al., 1990b). Although this inhibition has been correlated with the decreased activity of the 70 kDa S6 kinase (pp70^(S6K)), a known downstream effector of the IL-2 receptor, the FKBP12-rapamycin complex does not appear to interact directly with this kinase (Chung et al., 1992; Kuo et al., 1992). Similarly, in T-cells and other cell types, rapamycin blocks progression of the cell cycle by preventing the activation of the cyclin-dependent kinases p33^(cdk2) and p34^(cdc2), but an association of the drug-immunophilin complex with the kinases or their respective cyclins has not been demonstrated (Albers et al., 1993; Jayaraman and Marks, 1993; Morice et al., 1993).

In the budding yeast S. cerevisiae, rapamycin also causes an arrest in the G1 phase of the cell cycle through its binding to a highly conserved FKBP12 homologue (Heitman et al., 1991b). The toxicity of the drug for yeast cells has allowed, through genetic selection, the identification of two homologous genes, which, when mutated, render the cells rapamycin-resistant (Heitman et al., 1991a). This led to the proposal that the products of these genes, which show some amino acid homology to the catalytic domain of the p110 subunit of PI-3 kinase, are the Targets Of Rapamycin and hence to the designation of the genes as TOR1 and TOR2 (Kunz et al., 1993). Direct support for this proposal, however, has not been presented and how the TOR gene products confer sensitivity to rapamycin remains to be elucidated. Alternatively, it has been suggested that in the signaling pathway blocked by rapamycin, the TOR proteins, like the S6 kinase and the cyclin-dependent kinases, lie downstream from the direct target of the FKBP12-rapamycin complex (Albers et al., 1993; Helliwell et al., 1994). This model assumes that the TOR mutations lead to the constitutive activation of the TOR1 and TOR2 proteins.

Besides binding to calcineurin in a FK506-dependent manner, FKBP12 can also interact with calcium-channel proteins, the ryanodine receptor, which mediates calcium induced calcium released (Jayaraman et al., 1992; Timerman et al., 1993) and the inositol 1,4,5,-triphosphate (IP₃) receptor (A. Cameron, A. Kaplin, D. Sabatini, J. Steiner, S. Snyder, unpublished). These associations do not require FK506 or rapamycin; indeed these drugs dissociate the FKBP12-channel complex.

There is a need in the art to identify, isolate, and purify the mammalian cellular proteins that interact with FKBP12 only in the presence of rapamycin. Such proteins play a role in immunological, neurological, and cell cycle functions.

SUMMARY OF THE INVENTION

It is an object of the invention to provide isolated, purified cDNA molecules encoding rapamycin and FKBP target molecules.

It is another object of the invention to provide fusion proteins comprising rapamycin and FKBP targets.

It is still another object of the invention to provide an isolated and purified rapamycin and FKBP target molecule.

It is still another object of the invention to provide an expression construct which directs synthesis in a cell of an RNA molecule which inibits expression of a rapamycin and FKBP target molecule.

It is yet another object of the invention to provide isolated, purified cDNA molecules which are complementary to genes encoding rapamcyin and FKBP target molecules.

It is an object of the invention to provide a method of screening for potential therapeutic agents.

It is another object of the invention to provide a method of purifying a rapamycin and FKBP target molecule.

It is still another object of the invention to provide a method of isolating DNA sequences which code for rapamycin and FKBP target molecules.

These and other objects of the inveniton are provided by one or more of the embodiments described below. In one embodiment of the invention an isolated, purified cDNA molecule is provided which encodes RAFT1, a protein having the amino acid sequence shown in SEQ ID NO:1.

In another embodiment of the invention a fusion protein comprising the amino acid sequence shown in SEQ ID NO:1, is provided.

In yet another embodiment of the invention an isolated and purified RAFT1 protein having the amino acid sequence shown in SEQ ID NO:1 is provided. Also provided is an isolated and purified RAFT2 protein, having an apparent molecular weight on SDS polyacrylamide gels of 35 kDa. Also provided is an isolated and purified mammalian RAFT protein which is free of proteins which do not bind to rapamycin and FKBP12. Also provided is a mammalian RAFT protein prepared by the process of:

contacting a preparation of mammalian proteins with FKBP12 in the presence of rapamycin;

isolating mammalian proteins which bind to FKBP12 in the presence of rapamycin from those mammalian proteins which do not bind; and

dissociating bound mammalian proteins from FKBP12 to provide a mammalian RAFT protein.

In still another embodiment of the invention an expression construct is provided. The expression construct comprises a promoter operably linked to at least 20 nucleotides of the antisense strand of RAFT1 cDNA, said expression construct directing synthesis in a cell of an RNA molecule which is complementary to RAFT1 RNA.

In another embodiment of the invention an isolated, purified cDNA molecule comprising at least 20 nucleotides of the sequence of RAFT1 is provided.

In yet another embodiment of the invention a method of screening substances for potential as therapeutic agents is provided. The method comprises the steps of:

contacting a substance to be tested with three components: (a) FKBP12, (b) rapamycin, and (c) a protein selected from the group consisting of RAFT1 and RAFT2;

determining the amount of one of said components bound to the other components in the presence and absence of said substance; a substance which increases or decreases the amount of said component bound being a potential therapeutic agent.

In one embodiment of the invention a method of purifying a mammalian RAFT protein is provided. The method comprises the steps of:

contacting a preparation of mammalian proteins with FKBP12 in the presence of rapamycin;

isolating mammalian proteins which bind to FKBP12 in the presence of rapamycin from those mammalian proteins which do not bind;

dissociating bound mammalian proteins from FKBP12 to provide a mammalian RAFT protein.

In another embodiment of the invention methods of isolating mammalian RAFT DNA sequences are provided. One of the methods comprises:

probing a library of mammalian DNA sequences with a probe which comprises at least 15 contiguous nucleotides selected from the sequence of RAFT1 cDNA.

Another of the methods comprises:

amplifying a DNA sequence using at least one primer which comprises at least 10 contiguous nucleotides selected from the sequence of RAFT1 cDNA.

These and other embodiments of the invention provide the art with potent tools for identifying drugs useful in the treatment of immunological, neurological, and cell cycle-related diseases and defects.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows partial purification of the FKBP12-rapamycin target proteins from brain cytosol by heparin column chromatography.

A cytosolic fraction prepared from a rat brain homogenate was applied to a heparin column. The material that remained bound to the column after washing with 5 column volumes of wash buffer containing 200 mM KCl, was eluted with a linear gradient from 200 mM to 600 mM KCl in homogenization buffer. Aliquots of the crude cytosol (S), the column flow through (FT), and the wash (W) were tested in the crosslinking assay with (+) or without (−) rapamycin (100 nM). Every other fraction eluted from the heparin column was tested in the crosslinking assay in the presence of 100 nM rapamycin. No rapamycin specific crosslinked products are visible in the crude cytosol because of the high concentrations of endogenous FKBP12 present in the initial sample.

FIG. 2 shows FK506 and unlabeled FKBP12 prevent the rapamycin-dependent association of ³²P-FKBP12 to the target proteins.

FIG. 2A) The heparin column eluate containing the RAFTs was tested in the crosslinking assay at the indicated concentrations of rapamycin with or without the addition of 1 μM FK506 or 1 μM FKBP12. FIG. 2B) Neither FK506 alone nor the ethanol vehicle induce crosslinking of FKBP12 to RAFT. The heparin eluate containing RAFT was tested in the crosslinking assay with the indicated concentrations of FK506 or ethanol. This experiment was repeated twice with identical results.

FIG. 3 shows purification of RAFT1 with a FKBP12-rapamycin affinity column.

RAFT enriched fractions eluting from the heparin column between 300 and 450 mM KCl, were incubated in the presence (+) or absence (−) of 100 nM rapamycin with GST-(PKA)2-FKBP12 fusion protein (20 μg) immobilized on glutathione agarose beads. The material that remained associated with the beads after extensive washes was analyzed by SDS-PAGE (8%) and silver staining. RAFT1 is present only in the sample treated with rapamycin. The large band at 36 kDa is the GST-FKBP12 fusion protein.

FIGS. 4A through 4F shows alignment of RAFT1 amino acid sequence (SEQ ID NO:1) with the predicted amino acid sequences of TOR2 (SEQ ID NO:3) and TOR1 (SEQ ID NO:2).

The alignment was maximized by introducing insertions marked by dashes. Sequences in RAFT1 identical to TOR2 and/or TOR1 are indicated with gray shading. The sequences of tryptic peptides obtained by microsequencing are indicated with a line above the RAFT1 sequence. Sequences used to design primers for PCR are indicated with an arrow above the residues (direction indicate sense or antisense). The PKC site conserved between RAFT1, TOR1 and TOR2 is boxed.

FIG. 5 shows rapamycin-dependent crosslinking of FKBP12 to two PC12 cell cytosolic proteins of approximate molecular weight 245 kDa and 35 kDa.

³²P-labeled FKBP12 (10⁵ cpm) was incubated with cytosolic fractions from PC12 cells with or without the indicated concentration of rapamycin for 1 hr. at 4° C. The crosslinker DSS was then added and the incubation continued for 40 minutes before processing for SDS-PAGE (4%-12% gradient) and autoradiography. The arrows indicate the two bands that appear only in the presence of rapamycin. This experiment was repeated three times with identical results.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

We have isolated and identified proteins, which we designate RAFT1 and RAFT2, that interact with the FKBP12-rapamycin complex. Rapamycin-induced binding of FKBP12 to RAFT1 occurs at drug concentrations as low as 1 and 10 nM, resembling pharmacological potency in vivo (Bierer et al., 1990a; Dumont et al., 1990a). FK506 and rapamycin bind with similar affinities to the same binding site on FKBP12 and antagonize each others' actions in vivo (Bierer et al., 1990a; Dumont et al., 1990b). Consistent with these facts, FK506 does not induce interactions between FKBP12 and RAFT1 but, instead, prevents the rapamycin-mediated effect. Since rapamycin has pleiotropic effects on a wide variety of cell types, the target of its complex with FKBP12 is likely to be an early participant in several signal transduction pathways.

We have also isolated and purified a cDNA molecule which encodes RAFT1. The predicted amino acid sequence of the protein, which exactly corresponds to the empirically determined amino acid sequences of tryptic peptides of RAFT1, is shown in SEQ ID NO:1. The cDNA sequence can be used to express in recombinant cells RAFT1 proteins or portions of the RAFT1 protein. Similarly, the cDNA sequence can be used to construct fused genes which will express fusion proteins comprising all or part of the RAFT1 sequence. Having provided the art with the amino acid sequence of the RAFT1 protein, other coding sequences can be devised which differ from that isolated virtue of the degeneracy, of the genetic code. Such nucleotide sequences are within the scope of the present invention.

RAFT1 has an apparent molecular weight on SDS polyacrylamide gels of 245 kDa. RAFT2 has an apparent molecular weight on SDS polyacrylamide gels of 35 kDa. Isolated and purified RAFT1 protein can be obtained by means of recombinant DNA technology or by isolating and purifying the protein directly from natural sources. One means of purifying RAFTs involves contacting a preparation of mammalian proteins with FKBP12 in the presence of rapamycin. Those proteins which bind to FKBP12 in the presence of rapamycin can then be separated from those which do not bind. Bound proteins can then be dissociated to yield a preparation of a RAFT protein. It is convenient if the FKBP12 is immobilized, for example, on a solid support. One convenient means is to immobilize FKBP12 on a column-packing matrix. For example, an FKPB12-glutathione-S-transferase fusion protein can be readily bound to glutathione-agarose to provide immobilized FKBP12. Another means of purifying RAFT proteins is by use of a heparin chromatography column. The RAFT proteins bind to the heparin and can be eluted at 300 to 450 mM KCl.

Because of the role of rapamycin in immunological, cell cycle, and neurological functions, it may be desirable to inhibit the expression of RAFT1. One means to accomplish this is to use antisense polynucleotides. Antisense polynucleotides can be made synthetically. Alternatively, expression constructs may be used which comprise a promoter operably linked to at least 20 nucloetides of the antisense strand of RAFT1 cDNA. The expression construct directs the synthesis in a cell of an RNA molecule which is complementary to RAFT1 mRNA. Any suitable promoter can be used, depending on the cell system in which expression of the antisense molecule is desired.

The nucleotide sequence of RAFT1 can be used to generate probes which comprise at least 15-20 nucleotides of the recited sequence. These probes can be used to screen a library of mammalian DNA molecules. Techniques for making nucleotide probes and screening genomic or cDNA libraries are well known in the art. Alternatively, other RAFT nucleotide sequences can be obtained by amplification of mammalian DNA using as primers one or two polynucleotides comprising at least 10 contiguous nucleotides selected from the sequence of RAFT1. Techniques for amplification of DNA are also well known in the art.

RAFT1 and RAFT2 can be used to screen substances for potential as therapeutic agents for immunological, cell cycle, and neurological disease states. As described here, rapamycin, FKBP12, RAFT1, and RAFT2 bind to each other and form a complex. Test compounds can be screened for potential therapeutic utility by contacting a test compound with three components: (a) FKBP12; (b) rapamycin; and (c) a protein selected from the group consisting of RAFT1 and RAFT2. The amount of one of the components in the complex is determined, in the presence and in the absence of the substance to be tested. A substance which increases or decreasees the amount of the component in the complex is a potential therapeutic agent. Means used for determining amounts of components can be any known in the art, including the use of radioactive components, antibodies specific for components, densitometry, etc.

EXAMPLES

The following materials were used in the examples described below. Frozen rat brains stripped of the meninges were obtained from Harlan Bioproducts (Indianapolis, Ind.). Other materials were purchased from the following sources: [γ-³²P]-ATP (NEG-02z) from New England Nuclear (Cambridge, Mass.), glutathione-agarose, heart muscle kinase (PKA, #P2645), and heparin-agarose from Sigma Chemical (St. Louis, Mo.), thrombin and antithrombin from Boehringer Mannheim (Indianapolis, Ind.), and disuccinimidyl suberate (DSS) from Pierce (Rockford, Ill.). Rapamycin was a gift of the Wyeth-Ayerst company (Philadelphia, Pa.) and FK506 a gift of the Fujisawa company (Tsukuba City, Japan).

Example 1 Rapamycin Promotes the Binding of FKBP12 to Two Cytosolic Proteins of Mr 245 and 35 kDa

A ³²P-radiolabeled FKBP12 probe was used to detect proteins that associate with the immunophilin in the presence of ligand, and are crosslinked to it by the bivalent reagent DSS. The probe was prepared by phosphorylating with [γ ³²P]ATP a recombinant rat FKBP12 to which two consensus sites for cyclic AMP-dependent protein kinase (PKA) were added at the N-terminus (Blanar and Rutter, 1992; Li et al., 1992). Since this modification did not alter the capacity of the protein to associate with calcineurin in the presence of FK506. the probe can be used to identify a target of the FKBP12-rapamycin complex.

PC12 pheochromocytoma cell cytosolic extracts were incubated with ³²P-FKBP12 in the presence or absence of rapamycin and then treated with the crosslinker DSS before gel electrophoretic analysis followed by autoradiography. The drug caused the formation of two protein complexes with radioactive FKBP12, corresponding to bands of Mr 260 and 50 kDa (FIG. 5). Taking into account the 15 kDa Mr of the modified FKBP12 probe, the crosslinked proteins were estimated to be 245 kDa and 35 kDa, respectively. The crosslinked complexes were observed over a wide rapamycin concentration range, but were more prominent at the low concentrations of 1 and 10 nM, possibly because of an inhibitory effect on the association of the higher amounts of ethanol (the solvent of the drug) present at the higher drug concentrations (FIG. 5). Rapamycin also induced the formation of similar complexes when the probe was incubated with cytosolic extracts from several rat tissues, including liver, kidney, heart, small intestine, thymus, testes, spleen and brain, but no significant differences in abundance of the crosslinked proteins between the tissues were observed. For convenience, further experiments were carried out with whole brain extracts.

The formation of the rapamycin-dependent complexes was specific for FKBP12, since in similar experiments with the related immunophilin ³²P-FKBP25, no ligand induced complexes were observed.

PC12 cells were maintained in culture as described (Altin et al., 1991). PC12 cells were lysed in homogenization buffer with 0.3% NP-40 instead of CHAPS. Lysis was accomplished in 2 ml buffer/T-150 flask by repeated vortexing at 4° C. Cell debris was sedimented by centrifugation for 10,000×g for 10 minutes at 4° C.

The labeled, cleaved FKBP12 was diluted to 10,000 cpm/ml in 50 mM Hepes pH 7.5, 1 mg/ml BSA. 10 μl of labeled protein (100,000 cpm total), 10 μl of tissue or PC12 cell extract, and 10 μl of drug dilutant buffer (20 mM Hepes 6.8, 100 mM KCl, 1 mM EGTA, 1 mM DTT) containing either 3-fold the desired final concentration of rapamycin, FK506, or equivalent amounts of ethanol, were mixed and incubated for 1 hour at 4° C. After this incubation, 1 ml of 5.5 mg/ml disuccinimidyl suberate (DSS) was added and the incubation continued for 40 minutes. The reaction was terminated by adding one column volume of 2×concentrated sample buffer (Laemmlli, 1970) containing 50 mM Tris pH 7.4 and processed by SDS-PAGE (10%, unless otherwise specified) and autoradiography.

Example 2 Specificity of the Rapamycin Induced Association: the Interaction of ³²P-FKBP12-rapamycin with the 245 and 35 kDa Proteins is Competed by FK506 and by Unlabeled FKBP12

To investigate further the specificity of the interaction of ³²P-FKBP12-rapamycin with the cytosolic proteins, we performed a partial purification to remove endogenous FKBP12, which is present in brain at high concentrations (Steiner et al., 1992). This was accomplished by chromatography on a heparin column, to which the cytosolic proteins that interact with FKBP12-rapamycin bound and could be eluted at 300 to 450 mM KCl (FIG. 1). Free FKBP12, on the other hand, was recovered in the flow-through of this column, as demonstrated by binding to [³H]FK506 (data not shown).

The rat brain extract was applied to a heparin column (2 ml of packed heparin-agarose per brain) at a flow, rate of 1.5 ml/min. The column was washed with 10 column volumes of buffer (20 mM Hepes pH 6.8, 200 mM KCl, 1 mM EGTA, 50 mM NaF, 1.5 mM Na₃VO₄, 4 mM DTT, 1 mM PMSF) and the same protease inhibitors as in the homogenization buffer. The material bound to the column was eluted with a linear KCl gradient from 200 to 600 mM in homogenization buffer. Aliquots (10 μl) of the fractions collected were tested in the crosslinking assay and positive fractions were pooled and concentrated in a centriprep-100 (Amicon, Beverly, Mass.) to ⅓ starting volume. The flowthrough of the heparin column was assayed for the presence of FKBP with a ³H-FK506 binding assay, as described (Steiner et al, 1992).

FK506 antagonizes actions of rapamycin, and both drugs compete for the same binding site on FKBP12 (Bierer et al., 1990a; Dumont et al., 1990a). Accordingly, we examined the influence of FK506 on the rapamycin-induced interaction of ³²P-FKBP12 with its putative cytosolic targets. At concentrations ranging from 1 nM to 1 μM rapamycin induced the appearance of intense bands representing crosslinked proteins and, at all rapamycin concentrations tested, this effect was antagonized by 1 μM FK506 (FIG. 2A). As expected for ligands of similar affinity for FKBP12, when equal concentrations (1 μM) of rapamycin and FK506 were present, the intensities of the crosslinked bands were reduced by approximately 50% and the reduction progressively increased with increasing ratios of FK506/rapamycin. The heparin column eluate apparently contains limiting amounts of the putative targets of the FKBP12-rapamycin complex, since excess unlabeled FKBP12 (1 μM) completely suppressed the appearance of the crosslinked bands containing labeled FKBP12 (FIG. 2A).

Control experiments (FIG. 2B) confirmed the specificity of the rapamycin effect since the formation of the complex was not induced by several concentrations of FK506 or by ethanol, the solvent of the drugs. These experiments demonstrate that the crosslinked proteins are specific targets of the FKBP12-rapamycin complex and not of the FKBP12-FK506 complex, nor of FKBP12 alone. Therefore, we designate the crosslinked proteins RAFT1 (245 kDa) and RAFT2 (35 kDa) for Rapamycin And FKBP12 Target.

We attempted to separate RAFT1 and RAFT2 under nondenaturing conditions by several chromatography and gel filtration procedures. including DEAE and CM cellulose, reactive dye green 5, and Superose 6 (data not shown). All of these efforts failed, suggesting that RAFT1 and RAFT2 are part of a complex, although it is possible that RAFT2 is a proteolytic fragment of RAFT1 that contains the FKBP12-rapamycin binding site and remains tightly bound to the rest of the polypeptide.

Example 3 Purification of RAFT1

We purified RAFT1 from the heparin column eluate based on its affinity for FKBP12-rapamycin. We constructed a glutathione-S-transferase-FKBP12 fusion protein by cloning, in frame downstream of GST, a cDNA encoding FKBP12 with two N-terminal PKA consensus sites (Smith and Johnson, 1988; Blanar and Rutter, 1992; Li et al., 1992). The encoded protein was expressed in bacteria, purified and immobilized on glutathione-agarose beads. SDS-PAGE analysis of the beads recovered after incubating them with the heparin eluate in the presence or absence of rapamycin shows that the drug induces the binding to the beads of a protein of 245 kDa (FIG. 3). With this simple purification scheme we were able to purify about 5 μg of RAFT1. A low transfer efficiency to nitrocellulose membrane resulted in only 2.5 μg being available for protein sequencing, which corresponds to 10 picomoles of a protein of this size.

Standard techniques of molecular biology cloning were used as described (Sambrook et al., 1989) for the preparation of GST-(PKA)₂-FKBP12 and GST-(PKA)₂-FKBP25 fusion proteins, unless otherwise specified. All cDNAs obtained with the polymerase chain reaction were sequenced using the Sequenase kit (Amersham, Arlington Heights, Ill.). cDNAs for the rat FKBP12 and FKBP25 were obtained with the PCR using 5′ and 3′ primers to the corresponding human FKBP12 (Standaert et al., 1990) or FKBP25 (Jin et al., 1992) sequences. The cDNAs were cloned into pBluescript (Stratagene, La Jolla, Calif.).

A 5′ primer (PKA-12-1 or PKA-25-1) encoding a BamHI site, two consensus PKA phosphorylation sites (Blanar and Rutter, 1992; Li et al., 1992), and the first 6 amino acids of FKBP12 or FKBP25 was used with a 3′ primer (PKA-12-2 or PKA-25-2) encoding an EcoRI site and the last 6 codons of FKBP12 or FKBP25 in a PCR with Vent Polymerase (New England Biolabs, Beverly, Mass.) using the rat FKBPs cDNAs cloned in pBluescript as templates. The amplified DNA fragments were gel purified, digested with BamnH1 and EcoR1 and cloned into the pGEX-2T vector (Pharmacia, Upsala, Sweden) that had been linearized with the same restriction enzymes. The resulting construct was used to transform BL21 (DE3) E. coli (Novagen, Madison, Wis.) in which expression can be induced with IPTG. The primer sequences were is follows:

PKA-12-1:5′ CCGGATCCCGTCGAGCTTCAGTTGAACTACGGCGTGC TTCTGTAGCCATGGGAGTGCAGGTGGA 3′ (SEQ ID NO:4)

PKA-12-2: 5′ GGCCGGAATTCTCATTCCAGTTTTAGAA 3′ (SEQ ID NO:5)

PKA-25-1: 5′ CCGGATCCCGTCGAGCTTCAGTTGAACTACGGCGTGC TTCTGTAGCCATGGCGGCGGCCGTTCC 3′ (SEQ ID NO:10)

PKA-25-2: 5′ GGCCGGAATTCTCAATCAATATCCACTA 3′ (SEQ ID NO:11)

The fusion proteins were purified with glutathione-agarose as previously described (Smith and Johnson, 1988) from bacterial cultures induced with 1 mM IPTG.

The concentrated heparin column eluate was incubated for 2 hours at 4° C. with 1/50 volume of glutathione-agarose to remove endogenous glutathione binding proteins. The beads were removed by centrifugation at 1000×g for 3 minutes. Fresh glutathione-agarose (1/500 volume) and 20 μg of purified GST-PKA-FKBP12 fusion protein were then added to the cleared heparin column eluate with or without 100 nM rapamycin. After a 1 hour incubation at 4° C., the bead were washed 5× with 1.5 ml ice-cold PBS containing 1% Triton X-100 and 500 mM NaCl. The beads were transferred to 3×volume SDS-PAGE sample buffer, and the eluted proteins fractionated by SDS-PAGE and the gel silver stained.

Whether RAFT2 was also bound to the beads could not be determined in this experiment, because its presence would be masked by the large band of similar Mr corresponding to the GST-(PKA)₂-FKBP12 fusion protein. When smaller fusion proteins, such as an epitope-tagged FKBP12, were employed for the affinity matrix, the binding of the 35 kDa RAFT2 could also be observed.

The immunophilin fusion proteins containing N-terminal phosphorylation sites for PKA were labeled with a modification of published procedures (Blanar et. al., 1992, Li et. al., 1992). 10 ng of purified GST-PKA-FKBP12 or 25 was mixed with 40 units of PKA and 100 mCi of [γ-P³²]-ATP in a buffer containing 20 mM Hepes pH 7.7, 100 mM NaCl, 12 mM MgCl₂, 1 mM DTT.

After a 1.5 hour at 37° C. the incubation mixture containing labeled fusion protein was dialyzed twice against 1 L of thrombin cleavage buffer (50 mM Tris pH 7.4, 150 mM NaCl, 2.5 mM CaCl₂). The labeled fusion protein was cleaved by adding an equal volume of thrombin cleavage buffer containing 2 mg/ml thrombin and incubating at room temperature for 2 hours. The thrombin was inactivated by adding an equal volume of a stop solution consisting of 1 mM DTT, 1 mM PMSF, 100 units/ml antithrombin III. The specific activity of the probes was estimated at 1×10⁵ cpm/pmol of the protein.

Example 4 Protein Sequencing of RAFT1: Homology to TOR1 and TOR2

Affinity purified RAFT1 was separated by SDS-polyacrylamide gel electrophoresis from other proteins that adsorbed to the glutathione-agarose beads, transferred to nitrocellulose membrane, and digested with trypsin. Fractionation of the tryptic digest by narrow-bore reverse phase chromatography yielded a complex pattern of over a hundred peaks whose purity was assessed by mass spectroscopy. In most cases, the peaks exhibited multiple mass to charge peak values and it was necessary to rechromatograph these peak fractions on a microbore columns of different selectivity.

For protein sequence analysis affinity purified material derived from 50 brains was fractionated by SDS-PAGE and transferred to nitrocellulose membranes. The proteins transferred were visualized by Ponceau S staining, the 245 kDa RAFT1 band excised and processed for internal amino acid sequence analysis, essentially as described (Tempst et al., 1990).

Membrane-bound protein, about 2.5 μg, was subjected to in-situ proteolytic cleavage using 1 μg trypsin (Sequencing Grade; Boehringer-Mannheim) in 25 ml 100 mM NH₄HCO₃ (supplemented with 10% acetonitrile and 3% Tween-80) at 37° C. for 3 hours. The resulting peptide mixture was reduced and S-alkylated with, respectively, 0.1% β-mercapto ethanol and 0.3% 4-vinyl pyridine, and fractionated by two-dimensional reversed phase HPLC.

For the primary separations, a 2.1 mm Vydac C4 (214TP54) column was used with gradient elution at a flow rate of 100 μl/min. HPLC solvents and system configuration were as described (Tempst et al., 1990), with improved dead volume reduction through the use of glass capillary tubing (Elicone and Tempst, unpublished). Identification of Trp-containing peptides was done by manual ratio analysis of absorbances at 297 and 277 nm, monitored in real time using an Applied Biosystems model 1000S diode-array detector (Tempst et al., 1990). Fractions were collected by hand, kept on ice for the duration of the run and then stored at −70° C. before repurification and/or analysis. An enzyme blank was done on an equally sized strip of nitrocellulose cut from a blank area of the same blot. Repurifications (second dimension LC) were carried out on a 1.0 mm SGE ODS-2 C18 column using the same solvent system but at a flow rate of 30 μl/min. (C. Elicone, M. Lui, S. Geromanos, H. Erdjument-Bromage, P. Tempst, in press). Samples were always acidified (20% TFA final concentration) and then diluted twofold with 0.1% TFA before rechromatography.

Sequences of 23 peptides separated in this fashion were determined by a combination of automatic Edman degradation, matrix-assisted laser desorption mass-spectroscopy, and UV spectroscopy.

Peak fractions over background were analyzed by a combination of automated Edman degradation and matrix-assisted laser-desorption (MALDI-TOF) mass spectrometry (Geromanos et al., 1994; Elicone et al., 1994). After storage, column fractions were supplemented with neat TFA (to give a final concentration of 10%) before loading onto the sequencer disc and mass spectrometer probe tips. Peptide mass analysis (on 2% aliquots) was carried out using a model LaserTec ResearcH MALDI-TOF instrument (Vestec), with a 337 nm output nitrogen laser and 1.2 m flight tube. The matrix was a-cyano-4-hydroxy cinnamic acid, and a 28 kV ion acceleration and 4.3 kV multiplier voltage were used. Laser power and number of acquisitions were adjusted as judged from optimal deflections of specific maxima, using a Tektronix TDS 520 digitizing oscilloscope. M/z (mass to charge) spectra were generated from the time-of-flight files using GRAMS data analysis software. Every sample was analyzed twice, in the presence and absence of a calibrant (25 femtomoles APID), as described (Geromanos et al., 1994). Chemical sequencing (on 95% of the sample) was clone using a model 477A instrument from Applied Biosystems (AB). Stepwise liberated PTH-amino acids were identified using an “on-line” 120A HPLC system (AB) equipped with a PTH C18 (2.1×220 mm; 5 micron particle size) column (AB). Instruments and procedures were optimized for femtomole level phenyl thiohydantoin amino acid analysis as described (Tempst and Riviere, 1990; Erdjument-Bromage et al., 1993).

Peptide average isotopic masses were summed from the identified residues (including the presumed ones) using ProComp version 1.2 software (obtained from Dr. P. C. Andrews, University of Michigan, Ann Arbor, Mich.). Peptide sequences were compared to entries in various sequence databases using the National Center for Biotechnology Information (NCBI) BLAST program (Altschul et al. 1990). Lower stringency alignments between all peptides and selected proteins were done using the Lipman-Pearson algorithm, available in the ‘Lasergene’ software package (DNASTAR).

Several protein sequence databases (PIR, SwissProt, translated Genbank) were searched for sequences that match any of the 23 peptide sequences obtained from microsequencing of RAFT1. While sequence similarities with hundreds of different proteins were obtained for many of the 23 peptides, none perfectly matched with any of the entries in the databases, nor did any protein match more than one or two peptides, other than the yeast proteins TOR1 and TOR2 (Kunz et al., 1993). Strikingly, sixteen out of the 23 peptides of RAFT1 could be aligned with the yeast TOR sequences, with varying degrees of similarity (FIG. 4).

Example 5 Molecular Cloning of RAFT1

To generate a probe for isolating a RAFT1 cDNA two degenerate oligonucleotides were used in a mixed oligonucleotide polymerase chain reaction (PCR) (Gould et al, 1989) with rat brain cDNA as template. The sense primer was made to a peptide sequence (TYDPNQP, SEQ ID NO:6) obtained from microsequencing of RAFT1, while the antisense primer corresponds to a sequence (HIDFGD, SEQ ID NO:7) conserved between TOR1, TOR2, and p110 PI-3 Kinase. From the alignments of the RAFT1 peptides to the TORs, this sequence was expected to be 220 amino acids downstream of that encoded by the sense primer. The predicted 660 bp PCR product was obtained, cloned, and its authenticity was verified by DNA sequencing, which showed that it encoded two other sequenced tryptic peptides. The PCR product was, therefore, used as a probe (3′ probe) to screen a rat striatum cDNA library, which yielded a 5.5 kb partial cDNA clone. An antisense oligonucleotide to the extreme 5′ end of this cDNA was then used in a PCR reaction with a degenerate sense oligonucleotide to another peptide sequence (NDQVFE, SEQ ID NO:8) obtained from microsequencing. The predicted 1.1 kb PCR product was obtained, cloned and used as probe (5′ probe) to screen a rat brainstem cDNA library in parallel with the original 3′ probe. Phage plaques that hybridized with both probes were isolated and one was found to carry a 8.6 kb insert. A degenerate sense oligpnucleotide corresponding to the amino acid sequence TYDPNQP (SEQ ID NO:6), which was obtained from microsequencing of RAFT1 and aligns to residues 2086 to 2093 of TOR2, and a degenerate antisense primer corresponding to amino acids 2296 to 2301 (HIDFGD, SEQ ID NO:7) of TOR2 were used in a PCR reaction with rat whole brain cDNA as template. The protocol for the PCR was: an initial 5 min at 94° C., followed by 35 cycles of 94° C. for 40s, 56° C. for 1 min, 72° C. for 1 min, and a final incubation at 72° C. for 5 min. The PCR products were fractionated on a 1.1% agarose gel, the expected 700 bp DNA fragment purified and subcloned into pBluescript.

The RAFT-1 cDNA fragment in pBluescript was amplified by PCR, the product gel purified and labeled by nick translation with a commercial kit (Boehringer Mannheim). This probe (designated 3′ probe) was used to screen 1×10⁶ phage plaques of a rat striatum λ ZAP library (Stratagene), as described (Sambrook et al.). Forty seven positive clones were identified and 10 of them were purified by an additional two rounds of screening. None of the inserts contained a complete open reading frame. The 5′ end of the largest insert (5.5 kb) was used to design a 18 bp antisense oligdnucleotide (3.1 as) that was used in another PCR reaction with rat whole brain cDNA as template and a degenerate oligonucleotide corresponding to the amino acid sequence NDQVFE (SEQ ID NO:8, part of a peptide obtained from microsequencing) as the sense primer. The PCR products were fractionated on a 1% agarose gel and a DNA fragment of 1.1 kb isolated and cloned into the vector pCR-II using the TA cloning kit (Invitrogen, San Diego, Calif.). The cDNA fragment was amplified by PCR, the product gel purified and labeled by nick translation. This probe (designated 5′ probe) was used to screen 1×10⁶ phage plaques from a rat brainstem λ ZAP library. Duplicate filters were screened with the 3′ probe. Eight clones hybridized with both the 5′ and 3′ probes, and five of these were purified through 2 additional rounds of screening. One clone contained a 8.6 kb insert that encodes all 23 peptide sequences obtained by microsequencing.

PCR primer sequences were as follows:

TYDPNQP (SEQ ID NO:6): 5 ′-GGGGGATCCACNTA(C/T)GA(C/T)CCNAA(C/T) CA(A/G)C-3′ (SEQ ID NO:12)

HIDFGD (SEQ ID NO:7): 5 ′-GCGGAATTC(G/A)TCNCC(G/A)AA(G/A)TC(T/G/A) AT(G/A)TG-3′ (SEQ ID NO:13)

NDQVFE (SEQ ID NO:8): 5′-GGGGGATCCAA(C/T)GA(C/T)CA(G/A)GTNTT (T/C)GA-3′ (SEQ ID NO:14)

3.1as: 5′ -GAGCCACCACGATTTGCT-3′(SEQ ID NO:9)

cDNA clones were sequenced using the flourescent terminator method of cycle sequencing on a Applied Biosystems 373a automated DNA sequencer at the DNA analysis Facility of the Johns Hopkins University (Smith et al., 1986; McCombie et al, 1992), or with the dideoxy chain termination method using the Sequenase kit (Amersham, Arlington Heights, Ill.). Oligonucleotides used for sequencing were synthesized on an ABI 394 synthesizer following ABI protocols. DNA sequence data was analyzed using Sequencher software from Gene Codes (Ann Arbor, Mich.). Protein alignments were done with help from the e-mail service of the Computational Biochemistry Research Group (CBRG) at the ETH.

This cDNA contains an open reading frame of 7.6 kb with an initiation methionine codon that conforms to the Kozak consensus sequence (Kozak, 1986) and is preceded by an in-frame termination codon. The protein encoded by this open reading frame contains all 23 peptide sequences obtained by microsequencing of RAFT1 (FIG. 4). Interestingly, none of the peptides sequenced correspond to the C-terminal 250 amino acids of RAFT1, which may indicate that this portion of the protein was proteolytically removed during the purification.

The RAFT1 cDNA predicts a protein of 2550 amino acids with a molecular mass of 289 kDa and a PI of 6.8. Over its entire sequence RAFT1 is 43% identical to TOR2 and 39% identical to TOR1 (FIG. 4). The C-terminal 600 amino acids of RAFT1, which, by analogy to the TORs (Cafferkey et al., 1993; Kunz et al., 1993; Helliwell et al., 1994), is predicted to contain lipid kinase activities, is 65% identical to the yeast proteins. The RAFT1 protein has over 20 consensus sites for phosphorylation by protein kinase C (PKC), including one at serine₂₀₃₅, which is in the analogous position to the serine (S₁₉₇₂ in TOR1 and S₁₉₇₅ in TOR2) found mutated to arginine in rapamycin resistant yeast (boxed residues in FIG. 4).

The predicted RAFT1 protein is 80 amino acids longer than the TOR proteins, and contains several regions with no apparent homology to the yeast proteins, the largest being a 93 amino acid insertion corresponding to residues 270 to 363 of RAFT1. It is possible that these regions are generated by alternative splicing of exons that may be tissue specific to the brain. They are unlikely to be the translation product of unspliced introns because they were found in several cDNA clones isolated from different libraries and the DNA sequence does not reveal consensus splice junction sites.

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14 2549 amino acids amino acid linear protein YES NO Rattus rattus pheochromocytoma PC12 1 Met Leu Gly Thr Gly Pro Ala Thr Ala Thr Ala Gly Ala Ala Thr Ser 1 5 10 15 Ser Asn Val Ser Val Leu Gln Gln Phe Ala Ser Gly Leu Lys Ser Arg 20 25 30 Asn Glu Glu Thr Arg Ala Lys Ala Ala Lys Glu Leu Gln His Tyr Val 35 40 45 Thr Met Glu Leu Arg Glu Met Ser Gln Glu Glu Ser Thr Arg Phe Tyr 50 55 60 Asp Gln Leu Asn His His Ile Phe Glu Leu Val Ser Ser Ser Asp Ala 65 70 75 80 Asn Glu Arg Lys Gly Gly Ile Leu Ala Ile Ala Ser Leu Ile Gly Val 85 90 95 Glu Gly Gly Asn Ser Thr Arg Ile Gly Arg Phe Ala Asn Tyr Leu Arg 100 105 110 Asn Leu Leu Pro Ser Ser Asp Pro Val Val Met Glu Met Ala Ser Lys 115 120 125 Ala Ile Gly Arg Leu Ala Met Ala Gly Asp Thr Phe Thr Ala Glu Tyr 130 135 140 Val Glu Phe Glu Val Lys Arg Ala Leu Glu Trp Leu Gly Ala Asp Arg 145 150 155 160 Asn Glu Gly Arg Arg His Ala Ala Val Leu Val Leu Arg Glu Leu Ala 165 170 175 Ile Ser Val Pro Thr Phe Phe Phe Gln Gln Val Gln Pro Phe Phe Asp 180 185 190 Asn Ile Phe Val Ala Val Trp Asp Pro Lys Gln Ala Ile Arg Glu Gly 195 200 205 Ala Val Ala Ala Leu Arg Ala Cys Leu Ile Leu Thr Thr Gln Arg Glu 210 215 220 Pro Lys Glu Met Gln Lys Pro Gln Trp Tyr Arg His Thr Phe Glu Glu 225 230 235 240 Ala Glu Lys Gly Phe Asp Glu Thr Leu Ala Lys Glu Lys Gly Met Asn 245 250 255 Arg Asp Asp Arg Ile His Gly Ala Leu Leu Ile Leu Asn Glu Leu Val 260 265 270 Arg Ile Ser Ser Met Glu Gly Glu Arg Leu Arg Glu Glu Met Glu Glu 275 280 285 Ile Thr Gln Gln Gln Leu Val His Asp Lys Tyr Cys Lys Asp Leu Met 290 295 300 Gly Phe Gly Thr Lys Pro Arg His Ile Thr Pro Phe Thr Ser Phe Gln 305 310 315 320 Ala Val Gln Pro Gln Gln Ser Asn Ala Leu Val Gly Leu Leu Gly Tyr 325 330 335 Ser Ser His Gln Gly Leu Met Gly Phe Gly Ala Ser Pro Ser Pro Thr 340 345 350 Lys Ser Thr Leu Val Glu Ser Arg Cys Cys Arg Asp Leu Met Glu Glu 355 360 365 Lys Phe Asp Gln Val Cys Gln Trp Val Leu Lys Cys Arg Ser Ser Lys 370 375 380 Asn Ser Leu Ile Gln Met Thr Ile Leu Asn Leu Leu Pro Arg Leu Val 385 390 395 400 Ala Phe Arg Pro Ser Ala Phe Thr Asp Thr Gln Tyr Leu Gln Asp Thr 405 410 415 Met Asn His Val Leu Ser Cys Val Lys Lys Glu Lys Glu Arg Thr Ala 420 425 430 Ala Phe Gln Ala Leu Gly Leu Leu Ser Val Ala Val Arg Ser Glu Phe 435 440 445 Lys Val Tyr Leu Pro Arg Val Leu Asp Ile Ile Arg Ala Ala Leu Pro 450 455 460 Pro Lys Asp Phe Ala His Lys Arg Gln Lys Thr Val Gln Val Asp Ala 465 470 475 480 Thr Val Phe Thr Cys Ile Ser Met Leu Ala Arg Ala Met Gly Pro Gly 485 490 495 Ile Gln Gln Asp Ile Lys Glu Leu Leu Glu Pro Met Leu Ala Val Gly 500 505 510 Leu Ser Pro Ala Leu Thr Ala Val Leu Tyr Asp Leu Ser Arg Gln Ile 515 520 525 Pro Gln Leu Lys Lys Asp Ile Gln Asp Gly Leu Leu Lys Met Leu Ser 530 535 540 Leu Val Leu Met His Lys Pro Leu Arg His Pro Gly Met Pro Lys Gly 545 550 555 560 Leu Ala His Gln Leu Ala Ser Pro Gly Leu Thr Thr Leu Pro Glu Ala 565 570 575 Ser Asp Val Ala Ser Ile Thr Leu Ala Leu Arg Thr Leu Gly Ser Phe 580 585 590 Glu Phe Glu Gly His Ser Leu Thr Gln Phe Val Arg His Cys Ala Asp 595 600 605 His Phe Leu Asn Ser Glu His Lys Glu Ile Arg Met Glu Ala Ala Arg 610 615 620 Thr Cys Ser Arg Leu Leu Thr Pro Ser Ile His Leu Ile Ser Gly His 625 630 635 640 Ala His Val Val Ser Gln Thr Ala Val Gln Val Val Ala Asp Val Leu 645 650 655 Ser Lys Leu Leu Val Val Gly Ile Thr Asp Pro Asp Pro Asp Ile Arg 660 665 670 Tyr Cys Val Leu Ala Ser Leu Asp Glu Arg Phe Asp Ala His Leu Ala 675 680 685 Gln Ala Glu Asn Leu Gln Ala Leu Phe Val Ala Leu Asn Asp Gln Val 690 695 700 Phe Glu Ile Arg Glu Leu Ala Ile Cys Thr Val Gly Arg Leu Ser Ser 705 710 715 720 Met Asn Pro Ala Phe Val Met Pro Phe Leu Arg Lys Met Leu Ile Gln 725 730 735 Ile Leu Thr Glu Leu Glu His Ser Gly Ile Gly Arg Ile Lys Glu Gln 740 745 750 Ser Ala Arg Met Leu Gly His Leu Val Ser Asn Ala Pro Arg Leu Ile 755 760 765 Arg Pro Tyr Met Glu Pro Ile Leu Lys Ala Leu Ile Leu Lys Leu Lys 770 775 780 Asp Pro Asp Pro Asp Pro Asn Pro Gly Val Ile Asn Asn Val Leu Ala 785 790 795 800 Thr Ile Gly Glu Leu Ala Gln Val Ser Gly Leu Glu Met Arg Lys Trp 805 810 815 Val Asp Glu Leu Phe Val Ile Ile Met Asp Met Leu Gln Asp Ser Ser 820 825 830 Leu Leu Ala Lys Arg Gln Val Ala Leu Trp Thr Leu Gly Gln Leu Val 835 840 845 Ala Ser Thr Gly Tyr Val Val Glu Pro Tyr Arg Lys Tyr Pro Thr Leu 850 855 860 Leu Glu Val Leu Leu Asn Phe Leu Lys Thr Glu Gln Asn Gln Gly Thr 865 870 875 880 Arg Arg Glu Ala Ile Arg Val Leu Gly Leu Leu Gly Ala Leu Asp Pro 885 890 895 Tyr Lys His Lys Val Asn Ile Gly Met Ile Asp Gln Ser Arg Asp Ala 900 905 910 Ser Ala Val Ser Leu Ser Glu Ser Lys Ser Ser Gln Asp Ser Ser Asp 915 920 925 Tyr Ser Thr Ser Glu Met Leu Val Asn Met Gly Asn Leu Pro Leu Asp 930 935 940 Glu Phe Tyr Pro Ala Val Ser Met Val Ala Leu Met Arg Ile Phe Arg 945 950 955 960 Asp Gln Ser Leu Ser His His His Thr Met Val Val Gln Ala Ile Thr 965 970 975 Phe Ile Phe Lys Ser Leu Gly Leu Lys Cys Val Gln Phe Leu Pro Gln 980 985 990 Val Met Pro Thr Phe Leu Asn Val Ile Arg Val Cys Asp Gly Ala Ile 995 1000 1005 Arg Glu Phe Leu Phe Gln Gln Leu Gly Met Leu Val Ser Phe Val Lys 1010 1015 1020 Ser His Ile Arg Pro Tyr Met Asp Glu Ile Val Thr Leu Met Arg Glu 1025 1030 1035 1040 Phe Trp Val Met Asn Thr Ser Ile Gln Ser Thr Ile Ile Leu Leu Ile 1045 1050 1055 Glu Gln Ile Val Val Ala Leu Gly Gly Glu Phe Lys Leu Tyr Leu Pro 1060 1065 1070 Gln Leu Ile Pro His Met Leu Arg Val Phe Met His Asp Asn Ser Gln 1075 1080 1085 Gly Arg Ile Val Ser Ile Lys Leu Leu Ala Ala Ile Gln Leu Phe Gly 1090 1095 1100 Ala Asn Leu Asp Asp Tyr Leu His Leu Leu Leu Pro Pro Ile Val Lys 1105 1110 1115 1120 Leu Phe Asp Ala Pro Glu Val Pro Leu Pro Ser Arg Lys Ala Ala Leu 1125 1130 1135 Glu Thr Val Asp Arg Leu Thr Glu Ser Leu Asp Phe Thr Asp Tyr Ala 1140 1145 1150 Ser Arg Ile Ile His Pro Ile Val Arg Thr Leu Asp Gln Ser Pro Glu 1155 1160 1165 Leu Arg Ser Thr Ala Met Asp Thr Leu Ser Ser Leu Val Phe Gln Leu 1170 1175 1180 Gly Lys Lys Tyr Gln Ile Phe Ile Pro Met Val Asn Lys Val Leu Val 1185 1190 1195 1200 Arg His Arg Ile Asn His Gln Arg Tyr Asp Val Leu Ile Cys Arg Ile 1205 1210 1215 Val Lys Gly Tyr Thr Leu Ala Asp Glu Glu Glu Asp Pro Leu Ile Tyr 1220 1225 1230 Gln His Arg Met Leu Arg Ser Ser Gln Gly Asp Ala Leu Ala Ser Gly 1235 1240 1245 Pro Val Glu Thr Gly Pro Met Lys Lys Leu His Val Ser Thr Ile Asn 1250 1255 1260 Leu Gln Lys Ala Trp Gly Ala Ala Arg Arg Val Ser Lys Asp Asp Trp 1265 1270 1275 1280 Leu Glu Trp Leu Arg Arg Leu Ser Leu Glu Leu Leu Lys Asp Ser Ser 1285 1290 1295 Ser Pro Ser Leu Arg Ser Cys Trp Ala Leu Ala Gln Ala Tyr Asn Pro 1300 1305 1310 Met Ala Arg Asp Leu Phe Asn Ala Ala Phe Val Ser Cys Trp Ser Glu 1315 1320 1325 Leu Asn Glu Asp Gln Gln Asp Glu Leu Ile Arg Ser Ile Glu Leu Ala 1330 1335 1340 Leu Thr Ser Gln Asp Ile Ala Glu Val Thr Gln Thr Leu Leu Asn Leu 1345 1350 1355 1360 Ala Glu Phe Met Glu His Ser Asp Lys Gly Pro Leu Pro Leu Arg Asp 1365 1370 1375 Asp Asn Gly Ile Val Leu Leu Gly Glu Arg Ala Ala Lys Cys Arg Ala 1380 1385 1390 Tyr Ala Lys Ala Leu His Tyr Lys Glu Leu Glu Phe Gln Lys Gly Pro 1395 1400 1405 Thr Pro Ala Ile Leu Glu Ser Leu Ile Ser Ile Asn Asn Lys Leu Gln 1410 1415 1420 Gln Pro Glu Ala Ala Ser Gly Val Leu Glu Tyr Ala Met Lys His Phe 1425 1430 1435 1440 Gly Glu Leu Glu Ile Gln Ala Thr Trp Tyr Glu Lys Leu His Glu Trp 1445 1450 1455 Glu Asp Ala Leu Val Ala Tyr Asp Lys Lys Met Asp Thr Asn Lys Asp 1460 1465 1470 Asp Pro Glu Leu Met Leu Gly Arg Met Arg Cys Leu Glu Ala Leu Gly 1475 1480 1485 Glu Trp Gly Gln Leu His Gln Gln Cys Cys Glu Lys Trp Thr Leu Val 1490 1495 1500 Asn Asp Glu Thr Gln Ala Lys Met Ala Arg Met Ala Ala Ala Ala Ala 1505 1510 1515 1520 Trp Gly Leu Gly Gln Trp Asp Ser Met Glu Glu Tyr Thr Cys Met Ile 1525 1530 1535 Pro Arg Asp Thr His Asp Gly Ala Phe Tyr Arg Ala Val Leu Ala Leu 1540 1545 1550 His Gln Asp Leu Phe Ser Leu Ala Gln Gln Cys Ile Asp Lys Ala Arg 1555 1560 1565 Asp Leu Leu Asp Ala Glu Leu Thr Ala Met Ala Gly Glu Ser Tyr Ser 1570 1575 1580 Arg Ala Tyr Gly Ala Met Val Ser Cys His Met Leu Ser Glu Leu Glu 1585 1590 1595 1600 Glu Val Ile Gln Tyr Lys Leu Val Pro Glu Arg Arg Glu Ile Ile Arg 1605 1610 1615 Gln Ile Trp Trp Glu Arg Leu Gln Gly Cys Gln Arg Ile Val Glu Asp 1620 1625 1630 Trp Gln Lys Ile Leu Met Val Arg Ser Leu Val Val Ser Pro His Glu 1635 1640 1645 Asp Met Arg Thr Trp Leu Lys Tyr Ala Ser Leu Cys Gly Lys Ser Gly 1650 1655 1660 Arg Leu Ala Leu Ala His Lys Thr Leu Val Leu Leu Leu Gly Val Asp 1665 1670 1675 1680 Pro Ser Arg Gln Leu Asp His Pro Leu Pro Thr Val His Pro Gln Val 1685 1690 1695 Thr Tyr Ala Tyr Met Lys Asn Met Trp Lys Ser Ala Arg Lys Ile Asp 1700 1705 1710 Ala Phe Gln His Met Gln His Phe Val Gln Thr Met Gln Gln Gln Ala 1715 1720 1725 Gln His Ala Ile Ala Thr Glu Asp Gln Gln His Lys Gln Glu Leu His 1730 1735 1740 Lys Leu Met Ala Arg Cys Phe Leu Lys Leu Gly Glu Trp Gln Leu Asn 1745 1750 1755 1760 Leu Gln Gly Ile Asn Glu Ser Thr Ile Pro Lys Val Leu Gln Tyr Tyr 1765 1770 1775 Ser Ala Ala Thr Glu His Asp Arg Ser Trp Tyr Lys Ala Trp His Ala 1780 1785 1790 Trp Ala Val Met Asn Phe Glu Ala Val Leu His Tyr Lys His Gln Asn 1795 1800 1805 Gln Ala Arg Asp Glu Lys Lys Lys Leu Arg His Ala Ser Gly Ala Asn 1810 1815 1820 Ile Thr Asn Ala Thr Thr Thr Ala Thr Thr Ala Ala Ser Ala Ala Ala 1825 1830 1835 1840 Ala Thr Ser Thr Glu Gly Ser Asn Ser Glu Ser Glu Ala Glu Ser Asn 1845 1850 1855 Glu Ser Ser Pro Thr Pro Ser Pro Leu Gln Lys Lys Val Thr Glu Asp 1860 1865 1870 Leu Ser Lys Thr Leu Leu Leu Tyr Thr Val Pro Ala Val Gln Gly Phe 1875 1880 1885 Phe Arg Ser Ile Ser Leu Ser Arg Gly Asn Asn Leu Gln Asp Thr Leu 1890 1895 1900 Arg Val Leu Thr Leu Trp Phe Asp Tyr Gly His Trp Pro Asp Val Asn 1905 1910 1915 1920 Glu Ala Leu Val Glu Gly Val Lys Ala Ile Gln Ile Asp Thr Trp Leu 1925 1930 1935 Gln Val Ile Pro Gln Leu Ile Ala Arg Ile Asp Thr Pro Arg Pro Leu 1940 1945 1950 Val Gly Arg Leu Ile His Gln Leu Leu Thr Asp Ile Gly Arg Tyr His 1955 1960 1965 Pro Gln Ala Leu Ile Tyr Pro Leu Thr Val Ala Ser Lys Ser Thr Thr 1970 1975 1980 Thr Ala Arg His Asn Ala Ala Asn Lys Ile Leu Lys Asn Met Cys Glu 1985 1990 1995 2000 His Ser Asn Thr Leu Val Gln Gln Ala Met Met Val Ser Glu Glu Leu 2005 2010 2015 Ile Arg Val Ala Ile Leu Trp His Glu Met Trp His Glu Gly Leu Glu 2020 2025 2030 Glu Ala Ser Arg Leu Tyr Phe Gly Glu Arg Asn Val Lys Gly Met Phe 2035 2040 2045 Glu Val Leu Glu Pro Leu His Ala Met Met Glu Arg Gly Pro Gln Thr 2050 2055 2060 Leu Lys Glu Thr Ser Phe Asn Gln Ala Tyr Gly Arg Asp Leu Met Glu 2065 2070 2075 2080 Ala Gln Glu Trp Cys Arg Lys Tyr Met Lys Ser Gly Asn Val Lys Asp 2085 2090 2095 Leu Thr Gln Ala Trp Asp Leu Tyr Tyr His Val Phe Arg Arg Ile Ser 2100 2105 2110 Lys Gln Leu Pro Gln Leu Thr Ser Leu Glu Leu Gln Tyr Val Ser Pro 2115 2120 2125 Lys Leu Leu Met Cys Arg Asp Leu Glu Leu Ala Val Pro Gly Thr Tyr 2130 2135 2140 Asp Pro Asn Gln Thr Ile Ile Arg Ile Gln Ser Ile Ala Pro Ser Leu 2145 2150 2155 2160 Gln Val Ile Thr Ser Lys Gln Arg Pro Arg Lys Leu Thr Leu Met Gly 2165 2170 2175 Ser Asn Gly His Glu Phe Val Phe Leu Leu Lys Gly His Glu Asp Leu 2180 2185 2190 Arg Gln Asp Glu Arg Val Met Gln Leu Phe Gly Leu Val Asn Thr Leu 2195 2200 2205 Leu Ala Asn Asp Pro Thr Ser Leu Arg Lys Asn Leu Ser Ile Gln Arg 2210 2215 2220 Tyr Ala Val Ile Pro Leu Ser Thr Asn Ser Gly Leu Ile Gly Trp Val 2225 2230 2235 2240 Pro His Cys Asp Thr Leu His Ala Leu Ile Arg Asp Tyr Arg Glu Lys 2245 2250 2255 Lys Lys Ile Leu Leu Asn Ile Glu His Arg Ile Met Leu Arg Met Ala 2260 2265 2270 Pro Asp Tyr Asp His Leu Thr Leu Met Gln Lys Val Glu Val Phe Glu 2275 2280 2285 His Ala Val Asn Asn Thr Ala Gly Asp Asp Leu Ala Lys Leu Leu Trp 2290 2295 2300 Leu Lys Ser Pro Ser Ser Glu Val Trp Phe Asp Arg Arg Thr Asn Tyr 2305 2310 2315 2320 Thr Arg Ser Leu Ala Val Met Ser Met Val Gly Tyr Ile Leu Gly Leu 2325 2330 2335 Gly Asp Arg His Pro Ser Asn Leu Met Leu Asp Arg Leu Ser Gly Lys 2340 2345 2350 Ile Leu His Ile Asp Phe Gly Asp Cys Phe Glu Val Ala Met Thr Arg 2355 2360 2365 Glu Lys Phe Pro Glu Lys Ile Pro Phe Arg Leu Thr Arg Met Leu Thr 2370 2375 2380 Asn Ala Met Glu Val Thr Gly Leu Asp Arg Asn Tyr Arg Thr Thr Cys 2385 2390 2395 2400 His Thr Val Met Glu Val Leu Arg Glu His Lys Asp Ser Val Met Ala 2405 2410 2415 Val Leu Glu Ala Phe Val Tyr Asp Pro Leu Leu Asn Trp Arg Leu Met 2420 2425 2430 Asp Thr Asn Ala Lys Gly Asn Lys Arg Ser Arg Thr Arg Thr Asp Ser 2435 2440 2445 Tyr Ser Ala Gly Gln Ser Val Glu Ile Leu Asp Gly Val Glu Leu Gly 2450 2455 2460 Glu Pro Ala His Lys Lys Thr Gly Thr Thr Val Pro Glu Ser Ile His 2465 2470 2475 2480 Ser Phe Ile Gly Asp Gly Leu Val Lys Pro Glu Ala Leu Asn Lys Lys 2485 2490 2495 Ala Ile Gln Ile Ile Asn Arg Val Arg Asp Lys Leu Thr Gly Arg Asp 2500 2505 2510 Phe Ser His Asp Asp Thr Leu Asp Val Pro Thr Gln Val Glu Leu Leu 2515 2520 2525 Ile Lys Gln Ala Thr Ser His Glu Asn Leu Cys Gln Cys Tyr Ile Gly 2530 2535 2540 Trp Cys Pro Phe Trp 2545 2470 amino acids amino acid linear protein Saccharomyces cerevisiae 2 Met Glu Pro His Glu Glu Gln Ile Trp Lys Ser Lys Leu Leu Lys Ala 1 5 10 15 Ala Asn Asn Asp Met Asp Met Asp Arg Asn Val Pro Leu Ala Pro Asn 20 25 30 Leu Asn Val Asn Met Asn Met Lys Met Asn Ala Ser Arg Asn Gly Asp 35 40 45 Glu Phe Gly Leu Thr Ser Ser Arg Phe Gly Gly Val Val Ile Gly Ser 50 55 60 Asn Gly Asp Val Asn Phe Lys Pro Ile Leu Glu Lys Ile Phe Arg Glu 65 70 75 80 Leu Thr Ser Asp Tyr Lys Glu Glu Arg Lys Leu Ala Ser Ile Ser Leu 85 90 95 Phe Asp Leu Leu Val Ser Leu Glu His Glu Leu Ser Ile Glu Glu Phe 100 105 110 Gln Ala Ile Ser Asn Asp Ile Asn Asn Lys Ile Leu Glu Leu Val His 115 120 125 Thr Lys Lys Thr Asn Thr Arg Val Gly Ala Val Leu Ser Ile Asp Thr 130 135 140 Leu Ile Ser Phe Tyr Ala Tyr Thr Glu Arg Leu Pro Asn Glu Thr Ser 145 150 155 160 Arg Leu Ala Gly Tyr Leu Arg Gly Leu Ile Pro Ser Asn Asp Val Glu 165 170 175 Val Met Arg Leu Ala Ala Lys Thr Leu Gly Lys Leu Ala Val Pro Gly 180 185 190 Gly Thr Tyr Thr Ser Asp Phe Val Glu Phe Glu Ile Lys Ser Cys Leu 195 200 205 Glu Trp Leu Thr Ala Ser Thr Glu Lys Asn Ser Phe Ser Ser Ser Lys 210 215 220 Pro Asp His Ala Lys His Ala Ala Leu Leu Ile Ile Thr Ala Leu Ala 225 230 235 240 Glu Asn Cys Pro Tyr Leu Leu Tyr Gln Tyr Leu Asn Ser Ile Leu Asp 245 250 255 Asn Ile Trp Arg Ala Leu Arg Asp Pro His Leu Val Ile Arg Ile Asp 260 265 270 Ala Ser Ile Thr Leu Ala Lys Cys Leu Ser Thr Leu Arg Asn Arg Asp 275 280 285 Pro Gln Leu Thr Ser Gln Trp Val Gln Arg Leu Ala Thr Ser Cys Glu 290 295 300 Tyr Gly Phe Gln Val Asn Thr Leu Glu Cys Ile His Ala Ser Leu Leu 305 310 315 320 Val Tyr Lys Glu Ile Leu Phe Leu Lys Asp Pro Phe Leu Asn Gln Val 325 330 335 Phe Asp Gln Met Cys Leu Asn Cys Ile Ala Tyr Glu Asn His Lys Ala 340 345 350 Lys Met Ile Arg Glu Lys Ile Tyr Gln Ile Val Pro Leu Leu Ala Ser 355 360 365 Phe Asn Pro Gln Leu Phe Ala Gly Lys Tyr Leu His Gln Ile Met Asp 370 375 380 Asn Tyr Leu Glu Ile Leu Thr Asn Ala Pro Ala Lys Lys Ile Pro His 385 390 395 400 Leu Lys Asp Asp Lys Pro Gln Ile Leu Ile Ser Ile Gly Asp Ile Ala 405 410 415 Tyr Glu Val Gly Pro Asp Ile Ala Pro Tyr Val Lys Gln Ile Leu Asp 420 425 430 Tyr Ile Glu His Asp Leu Gln Thr Lys Phe Lys Phe Arg Lys Lys Phe 435 440 445 Glu Asn Glu Ile Phe Tyr Cys Ile Gly Arg Leu Ala Val Pro Leu Gly 450 455 460 Pro Val Leu Gly Lys Leu Leu Asn Arg Asn Ile Leu Asp Leu Met Phe 465 470 475 480 Lys Cys Pro Leu Ser Asp Tyr Met Gln Glu Thr Phe Gln Ile Leu Thr 485 490 495 Glu Arg Ile Pro Ser Leu Gly Pro Lys Ile Asn Asp Glu Leu Leu Asn 500 505 510 Leu Val Cys Ser Thr Leu Ser Gly Thr Pro Phe Ile Gln Pro Gly Ser 515 520 525 Pro Met Glu Ile Pro Ser Phe Ser Arg Glu Arg Ala Arg Glu Trp Arg 530 535 540 Asn Lys Ser Ile Leu Gln Lys Thr Gly Glu Ser Asn Asp Asp Asn Asn 545 550 555 560 Asp Ile Lys Ile Ile Ile Gln Ala Phe Arg Met Leu Lys Asn Ile Lys 565 570 575 Ser Arg Phe Ser Leu Val Glu Phe Val Arg Ile Val Ala Leu Ser Tyr 580 585 590 Ile Glu His Thr Asp Pro Arg Val Arg Lys Leu Ala Ala Leu Thr Ser 595 600 605 Cys Glu Ile Tyr Val Lys Asp Asn Ile Cys Lys Gln Thr Ser Leu His 610 615 620 Ser Leu Asn Thr Val Ser Glu Val Leu Ser Lys Leu Leu Ala Ile Thr 625 630 635 640 Ile Ala Asp Pro Leu Gln Asp Ile Arg Leu Glu Val Leu Lys Asn Leu 645 650 655 Asn Pro Cys Phe Asp Pro Gln Leu Ala Gln Pro Asp Asn Leu Arg Leu 660 665 670 Leu Phe Thr Ala Leu His Asp Glu Ser Phe Asn Ile Gln Ser Val Ala 675 680 685 Met Glu Leu Val Gly Arg Leu Ser Ser Val Asn Pro Ala Tyr Val Ile 690 695 700 Pro Ser Ile Arg Lys Ile Leu Leu Glu Leu Leu Thr Lys Leu Lys Phe 705 710 715 720 Ser Thr Ser Ser Arg Glu Lys Glu Glu Thr Ala Ser Leu Leu Cys Thr 725 730 735 Leu Ile Arg Ser Ser Lys Asp Val Ala Lys Pro Tyr Ile Glu Pro Leu 740 745 750 Leu Asn Val Leu Leu Pro Lys Phe Gln Asp Thr Ser Ser Thr Val Ala 755 760 765 Ser Thr Ala Leu Arg Thr Ile Gly Glu Leu Ser Val Val Gly Gly Glu 770 775 780 Asp Met Lys Ile Tyr Leu Lys Asp Leu Phe Pro Leu Ile Ile Lys Thr 785 790 795 800 Phe Gln Asp Gln Ser Asn Ser Phe Lys Arg Glu Ala Ala Leu Lys Ala 805 810 815 Leu Gly Gln Leu Ala Ala Ser Ser Gly Tyr Val Ile Asp Pro Leu Leu 820 825 830 Asp Tyr Pro Glu Leu Leu Gly Ile Leu Val Asn Ile Leu Lys Thr Glu 835 840 845 Asn Ser Gln Asn Ile Arg Arg Gln Thr Val Thr Leu Ile Gly Ile Leu 850 855 860 Gly Ala Ile Asp Pro Tyr Arg Gln Lys Glu Arg Glu Val Thr Ser Thr 865 870 875 880 Thr Asp Ile Ser Thr Glu Gln Asn Ala Pro Pro Ile Asp Ile Ala Leu 885 890 895 Leu Met Gln Gly Met Ser Pro Ser Asn Asp Glu Tyr Tyr Thr Thr Val 900 905 910 Val Ile His Cys Leu Leu Lys Ile Leu Lys Asp Pro Ser Leu Ser Ser 915 920 925 Tyr His Thr Ala Val Ile Gln Ala Ile Met His Ile Phe Gln Thr Leu 930 935 940 Gly Leu Lys Cys Val Ser Phe Leu Asp Gln Ile Ile Pro Thr Ile Leu 945 950 955 960 Asp Val Met Arg Thr Cys Ser Gln Ser Leu Leu Glu Phe Tyr Phe Gln 965 970 975 Gln Leu Cys Ser Leu Ile Ile Ile Val Arg Gln His Ile Arg Pro His 980 985 990 Val Asp Ser Ile Phe Gln Ala Ile Lys Asp Phe Ser Ser Val Ala Lys 995 1000 1005 Leu Gln Ile Thr Leu Val Ser Val Ile Glu Ala Ile Ser Lys Ala Leu 1010 1015 1020 Glu Gly Glu Phe Lys Arg Leu Val Pro Leu Thr Leu Thr Leu Phe Leu 1025 1030 1035 1040 Val Ile Leu Glu Asn Asp Lys Ser Ser Asp Lys Val Leu Ser Arg Arg 1045 1050 1055 Val Leu Arg Leu Leu Glu Ser Phe Gly Pro Asn Leu Glu Gly Tyr Ser 1060 1065 1070 His Leu Ile Thr Pro Lys Ile Val Gln Met Ala Glu Phe Thr Ser Gly 1075 1080 1085 Asn Leu Gln Arg Ser Ala Ile Ile Thr Ile Gly Lys Leu Ala Lys Asp 1090 1095 1100 Val Asp Leu Phe Glu Met Ser Ser Arg Ile Val His Ser Leu Leu Arg 1105 1110 1115 1120 Val Leu Ser Ser Thr Thr Ser Asp Glu Leu Ser Lys Val Ile Met Asn 1125 1130 1135 Thr Leu Ser Leu Leu Leu Ile Gln Met Gly Thr Ser Phe Ala Ile Phe 1140 1145 1150 Ile Pro Val Ile Asn Glu Val Leu Met Lys Lys His Ile Gln His Thr 1155 1160 1165 Ile Tyr Asp Asp Leu Thr Asn Arg Ile Leu Asn Asn Asp Val Leu Pro 1170 1175 1180 Thr Lys Ile Leu Glu Ala Asn Thr Thr Asp Tyr Lys Pro Ala Glu Gln 1185 1190 1195 1200 Met Glu Ala Ala Asp Ala Gly Val Ala Lys Leu Pro Ile Asn Gln Ser 1205 1210 1215 Val Leu Lys Ser Ala Trp Asn Ser Ser Gln Gln Arg Thr Lys Glu Asp 1220 1225 1230 Trp Gln Glu Trp Ser Lys Arg Leu Ser Ile Gln Leu Leu Lys Glu Ser 1235 1240 1245 Pro Ser His Ala Leu Arg Ala Cys Ser Asn Leu Ala Ser Met Tyr Tyr 1250 1255 1260 Pro Leu Ala Lys Glu Leu Phe Asn Thr Ala Phe Ala Cys Val Trp Thr 1265 1270 1275 1280 Glu Leu Tyr Ser Gln Tyr Gln Glu Asp Leu Ile Gly Ser Leu Cys Ile 1285 1290 1295 Ala Leu Ser Ser Pro Leu Asn Pro Pro Glu Ile His Gln Thr Leu Leu 1300 1305 1310 Asn Leu Val Glu Phe Met Glu His Asp Asp Lys Ala Leu Pro Ile Pro 1315 1320 1325 Thr Gln Ser Leu Gly Glu Tyr Ala Glu Arg Cys His Ala Tyr Ala Lys 1330 1335 1340 Ala Leu His Tyr Lys Glu Ile Lys Phe Ile Lys Glu Pro Glu Asn Ser 1345 1350 1355 1360 Thr Ile Glu Ser Leu Ile Ser Ile Asn Asn Gln Leu Asn Gln Thr Asp 1365 1370 1375 Ala Ala Ile Gly Ile Leu Lys His Ala Gln Gln His His Ser Leu Gln 1380 1385 1390 Leu Lys Glu Thr Trp Phe Glu Lys Leu Glu Arg Trp Glu Asp Ala Leu 1395 1400 1405 His Ala Tyr Asn Glu Arg Glu Lys Ala Gly Asp Thr Ser Val Ser Val 1410 1415 1420 Thr Leu Gly Lys Met Arg Ser Leu His Ala Leu Gly Glu Trp Glu Gln 1425 1430 1435 1440 Leu Ser Gln Leu Ala Ala Arg Lys Trp Lys Val Ser Lys Leu Gln Thr 1445 1450 1455 Lys Lys Leu Ile Ala Pro Leu Ala Ala Gly Ala Arg Trp Gly Leu Gly 1460 1465 1470 Glu Trp Asp Met Leu Glu Gln Tyr Ile Ser Val Met Lys Pro Lys Ser 1475 1480 1485 Pro Asp Lys Glu Phe Phe Asp Ala Ile Leu Tyr Leu His Lys Asn Asp 1490 1495 1500 Tyr Asp Asn Ala Ser Lys His Ile Leu Asn Ala Arg Asp Leu Leu Val 1505 1510 1515 1520 Thr Glu Ile Ser Ala Leu Ile Asn Glu Ser Tyr Asn Arg Ala Tyr Ser 1525 1530 1535 Val Ile Val Arg Thr Gln Ile Ile Thr Glu Phe Glu Glu Ile Ile Lys 1540 1545 1550 Tyr Lys Gln Leu Pro Pro Asn Ser Glu Lys Lys Leu His Tyr Gln Asn 1555 1560 1565 Leu Trp Thr Lys Arg Leu Leu Gly Cys Gln Lys Asn Val Asp Leu Trp 1570 1575 1580 Gln Arg Val Leu Arg Val Arg Ser Leu Val Ile Lys Pro Lys Gln Asp 1585 1590 1595 1600 Leu Gln Ile Trp Ile Lys Phe Ala Asn Leu Cys Arg Lys Ser Gly Arg 1605 1610 1615 Met Arg Leu Ala Asn Lys Ala Leu Asn Met Leu Leu Glu Gly Gly Asn 1620 1625 1630 Asp Pro Ser Leu Pro Asn Thr Val Lys Ala Pro Pro Pro Val Val Tyr 1635 1640 1645 Ala Gln Leu Lys Tyr Ile Trp Ala Thr Gly Ala Tyr Lys Glu Ala Leu 1650 1655 1660 Asn His Leu Ile Gly Phe Thr Ser Arg Leu Ala His Asp Leu Gly Leu 1665 1670 1675 1680 Asp Pro Asn Asn Met Ile Ala Gln Ser Val Lys Leu Ser Ser Ala Ser 1685 1690 1695 Thr Ala Pro Tyr Val Glu Glu Tyr Thr Lys Leu Leu Ala Arg Cys Phe 1700 1705 1710 Leu Lys Gln Gly Glu Trp Arg Ile Ala Thr Gln Pro Asn Trp Arg Asn 1715 1720 1725 Thr Asn Pro Asp Ala Ile Leu Gly Ser Tyr Leu Leu Ala Thr His Phe 1730 1735 1740 Asp Lys Asn Trp Tyr Lys Ala Trp His Asn Trp Ala Leu Ala Asn Phe 1745 1750 1755 1760 Glu Val Ile Ser Met Val Gln Glu Glu Thr Lys Leu Asn Gly Gly Lys 1765 1770 1775 Asn Asp Asp Asp Asp Asp Thr Ala Val Asn Asn Asp Asn Val Arg Ile 1780 1785 1790 Asp Gly Ser Ile Leu Gly Ser Gly Ser Leu Thr Ile Asn Gly Asn Arg 1795 1800 1805 Tyr Pro Leu Glu Leu Ile Gln Arg His Val Val Pro Ala Ile Lys Gly 1810 1815 1820 Phe Phe His Ser Ile Ser Leu Leu Glu Thr Ser Cys Leu Gln Asp Thr 1825 1830 1835 1840 Leu Arg Leu Leu Thr Leu Leu Phe Asn Phe Gly Gly Ile Lys Glu Val 1845 1850 1855 Ser Gln Ala Met Tyr Glu Gly Phe Asn Leu Met Lys Ile Glu Asn Trp 1860 1865 1870 Leu Glu Val Leu Pro Gln Leu Ile Ser Arg Ile His Gln Pro Asp Pro 1875 1880 1885 Thr Val Ser Asn Ser Leu Leu Ser Leu Leu Ser Asp Leu Gly Lys Ala 1890 1895 1900 His Pro Gln Ala Leu Val Tyr Pro Leu Thr Val Ala Ile Lys Ser Glu 1905 1910 1915 1920 Ser Val Ser Arg Gln Lys Ala Ala Leu Ser Ile Ile Glu Lys Ile Arg 1925 1930 1935 Ile His Ser Pro Val Leu Val Asn Gln Ala Glu Leu Val Ser His Glu 1940 1945 1950 Leu Ile Arg Val Ala Val Leu Trp His Glu Leu Trp Tyr Glu Gly Leu 1955 1960 1965 Glu Asp Ala Arg Arg Gln Phe Phe Val Glu His Asn Ile Glu Lys Met 1970 1975 1980 Phe Ser Thr Leu Glu Pro Leu His Lys His Leu Gly Asn Glu Pro Gln 1985 1990 1995 2000 Thr Leu Ser Glu Val Ser Phe Gln Lys Ser Phe Gly Arg Asp Leu Asn 2005 2010 2015 Asp Ala Tyr Glu Trp Leu Asn Asn Tyr Lys Lys Ser Lys Asp Ile Asn 2020 2025 2030 Asn Leu Asn Gln Ala Trp Asp Ile Tyr Tyr Asn Val Phe Arg Lys Ile 2035 2040 2045 Thr Arg Gln Ile Pro Gln Leu Gln Thr Leu Asp Leu Gln His Val Ser 2050 2055 2060 Pro Gln Leu Leu Ala Thr His Asp Leu Glu Leu Ala Val Pro Gly Thr 2065 2070 2075 2080 Tyr Phe Pro Gly Lys Pro Thr Ile Arg Ile Ala Lys Phe Glu Pro Leu 2085 2090 2095 Phe Ser Val Ile Ser Ser Lys Gln Arg Pro Arg Lys Phe Ser Ile Lys 2100 2105 2110 Gly Ser Asp Gly Lys Asp Tyr Lys Tyr Val Leu Lys Gly His Glu Asp 2115 2120 2125 Ile Arg Gln Asp Ser Leu Val Met Gln Leu Phe Gly Leu Val Asn Thr 2130 2135 2140 Leu Leu Lys Asn Asp Ser Glu Cys Phe Lys Arg His Leu Asp Ile Gln 2145 2150 2155 2160 Gln Tyr Pro Ala Ile Pro Leu Ser Pro Lys Ser Gly Leu Leu Gly Trp 2165 2170 2175 Val Pro Asn Ser Asp Thr Phe His Val Leu Ile Arg Glu His Arg Asp 2180 2185 2190 Ala Lys Lys Ile Pro Leu Asn Ile Glu Gln Trp Val Met Leu Gln Met 2195 2200 2205 Ala Pro Asp Tyr Glu Asn Leu Thr Leu Leu Gln Lys Ile Glu Val Phe 2210 2215 2220 Thr Tyr Ala Leu Asp Asn Thr Lys Gly Gln Asp Leu Tyr Lys Ile Leu 2225 2230 2235 2240 Trp Leu Lys Ser Arg Ser Ser Glu Thr Trp Leu Glu Arg Arg Thr Thr 2245 2250 2255 Tyr Thr Arg Ser Leu Ala Val Met Ser Met Thr Gly Tyr Ile Leu Gly 2260 2265 2270 Leu Gly Asp Arg His Pro Ser Asn Leu Met Leu Asp Arg Ile Thr Gly 2275 2280 2285 Lys Val Ile His Ile Asp Phe Gly Asp Cys Phe Glu Ala Ala Ile Leu 2290 2295 2300 Arg Glu Lys Tyr Pro Glu Lys Val Pro Phe Arg Leu Thr Arg Met Leu 2305 2310 2315 2320 Thr Tyr Ala Met Glu Val Ser Gly Ile Glu Gly Ser Phe Arg Ile Thr 2325 2330 2335 Cys Glu Asn Val Met Arg Val Leu Arg Asp Asn Lys Glu Ser Leu Met 2340 2345 2350 Ala Ile Leu Glu Ala Phe Ala Leu Asp Pro Leu Ile His Trp Gly Phe 2355 2360 2365 Asp Leu Pro Pro Gln Lys Leu Thr Glu Gln Thr Gly Ile Pro Leu Pro 2370 2375 2380 Leu Ile Asn Pro Ser Glu Leu Leu Arg Lys Gly Ala Ile Thr Val Glu 2385 2390 2395 2400 Glu Ala Ala Asn Met Glu Ala Glu Gln Gln Asn Glu Thr Arg Asn Ala 2405 2410 2415 Arg Ala Met Leu Val Leu Arg Arg Ile Thr Asp Lys Leu Thr Gly Asn 2420 2425 2430 Asp Ile Lys Arg Phe Asn Glu Leu Asp Val Pro Glu Gln Val Asp Lys 2435 2440 2445 Leu Ile Gln Gln Ala Thr Ser Ile Glu Arg Leu Cys Gln His Tyr Ile 2450 2455 2460 Gly Trp Cys Pro Phe Trp 2465 2470 2474 amino acids amino acid linear protein Saccharomyces cerevisiae 3 Met Asn Lys Tyr Ile Asn Lys Tyr Thr Thr Pro Pro Asn Leu Leu Ser 1 5 10 15 Leu Arg Gln Arg Ala Glu Gly Lys His Arg Thr Arg Lys Lys Leu Thr 20 25 30 His Lys Ser His Ser His Asp Asp Glu Met Ser Thr Thr Ser Asn Thr 35 40 45 Asp Ser Asn His Asn Gly Pro Asn Asp Ser Gly Arg Val Ile Thr Gly 50 55 60 Ser Ala Gly His Ile Gly Lys Ile Ser Phe Val Asp Ser Glu Leu Asp 65 70 75 80 Thr Thr Phe Ser Thr Leu Asn Leu Ile Phe Asp Lys Leu Lys Ser Asp 85 90 95 Val Pro Gln Glu Arg Ala Ser Gly Ala Asn Glu Leu Ser Thr Thr Leu 100 105 110 Thr Ser Leu Ala Arg Glu Val Ser Ala Glu Gln Phe Gln Arg Phe Ser 115 120 125 Asn Ser Leu Asn Asn Lys Ile Phe Glu Leu Ile His Gly Phe Thr Ser 130 135 140 Ser Glu Lys Ile Gly Gly Ile Leu Ala Val Asp Thr Leu Ile Ser Phe 145 150 155 160 Tyr Leu Ser Thr Glu Glu Leu Pro Asn Gln Thr Ser Arg Leu Ala Asn 165 170 175 Tyr Leu Arg Val Leu Ile Pro Ser Ser Asp Ile Glu Val Met Arg Leu 180 185 190 Ala Ala Asn Thr Leu Gly Arg Leu Thr Val Pro Gly Gly Thr Leu Thr 195 200 205 Ser Asp Phe Val Glu Phe Glu Val Arg Thr Cys Ile Asp Trp Leu Thr 210 215 220 Leu Thr Ala Asp Asn Asn Ser Ser Ser Ser Lys Leu Glu Tyr Arg Arg 225 230 235 240 His Ala Ala Leu Leu Ile Ile Lys Ala Leu Ala Asp Asn Ser Pro Tyr 245 250 255 Leu Leu Tyr Pro Tyr Val Asn Ser Ile Leu Asp Asn Ile Trp Val Pro 260 265 270 Leu Arg Asp Ala Lys Leu Ile Ile Arg Leu Asp Ala Ala Val Ala Leu 275 280 285 Gly Lys Cys Leu Thr Ile Ile Gln Asp Arg Asp Pro Ala Leu Gly Lys 290 295 300 Gln Trp Phe Gln Arg Leu Phe Gln Gly Cys Thr His Gly Leu Ser Leu 305 310 315 320 Asn Thr Asn Asp Ser Val His Ala Thr Leu Leu Val Phe Arg Glu Leu 325 330 335 Leu Ser Leu Lys Ala Pro Tyr Leu Arg Asp Lys Tyr Asp Asp Ile Tyr 340 345 350 Lys Ser Thr Met Lys Tyr Lys Glu Tyr Lys Phe Asp Val Ile Arg Arg 355 360 365 Glu Val Tyr Ala Ile Leu Pro Leu Leu Ala Ala Phe Asp Pro Ala Ile 370 375 380 Phe Thr Lys Lys Tyr Leu Asp Arg Ile Met Val His Tyr Leu Arg Tyr 385 390 395 400 Leu Lys Asn Ile Asp Met Asn Ala Ala Asn Asn Ser Asp Lys Pro Phe 405 410 415 Ile Leu Val Ser Ile Gly Asp Ile Ala Phe Glu Val Gly Ser Ser Ile 420 425 430 Ser Pro Tyr Met Thr Leu Ile Leu Asp Asn Ile Arg Glu Gly Leu Arg 435 440 445 Thr Lys Phe Lys Val Arg Lys Gln Phe Glu Lys Asp Leu Phe Tyr Cys 450 455 460 Ile Gly Lys Leu Ala Cys Ala Leu Gly Pro Ala Phe Ala Lys His Leu 465 470 475 480 Asn Lys Asp Leu Leu Asn Leu Met Leu Asn Cys Pro Met Ser Asp His 485 490 495 Met Gln Glu Thr Leu Met Ile Leu Asn Glu Lys Ile Pro Ser Leu Glu 500 505 510 Ser Thr Val Asn Ser Arg Ile Leu Asn Leu Leu Ser Ile Ser Leu Ser 515 520 525 Gly Glu Lys Phe Ile Gln Ser Asn Gln Tyr Asp Phe Asn Asn Gln Phe 530 535 540 Ser Ile Glu Lys Ala Arg Lys Ser Arg Asn Gln Ser Phe Met Lys Lys 545 550 555 560 Thr Gly Glu Ser Asn Asp Asp Ile Thr Asp Ala Gln Ile Leu Ile Gln 565 570 575 Cys Phe Lys Met Leu Gln Leu Ile His His Gln Tyr Ser Leu Thr Glu 580 585 590 Phe Val Arg Leu Ile Thr Ile Ser Tyr Ile Glu His Glu Asp Ser Ser 595 600 605 Val Arg Lys Leu Ala Ala Leu Thr Ser Cys Asp Leu Phe Ile Lys Asp 610 615 620 Asp Ile Cys Lys Gln Thr Ser Val His Ala Leu His Ser Val Ser Glu 625 630 635 640 Val Leu Ser Lys Leu Leu Met Ile Ala Ile Thr Asp Pro Val Ala Glu 645 650 655 Ile Arg Leu Glu Ile Leu Gln His Leu Gly Ser Asn Phe Asp Pro Gln 660 665 670 Leu Ala Gln Pro Asp Asn Leu Arg Leu Leu Phe Met Ala Leu Asn Asp 675 680 685 Glu Ile Phe Gly Ile Gln Leu Glu Ala Ile Lys Ile Ile Gly Arg Leu 690 695 700 Ser Ser Val Asn Pro Ala Tyr Val Val Pro Ser Leu Arg Lys Thr Leu 705 710 715 720 Leu Glu Leu Leu Thr Gln Leu Lys Phe Ser Asn Met Pro Lys Lys Lys 725 730 735 Glu Glu Ser Ala Thr Leu Leu Cys Thr Leu Ile Asn Ser Ser Asp Glu 740 745 750 Val Ala Lys Pro Tyr Ile Asp Pro Ile Leu Asp Val Ile Leu Pro Lys 755 760 765 Cys Gln Asp Ala Ser Ser Ala Val Ala Ser Thr Ala Leu Lys Val Leu 770 775 780 Gly Glu Leu Ser Val Val Gly Gly Lys Glu Met Thr Arg Tyr Leu Lys 785 790 795 800 Glu Leu Met Pro Leu Ile Ile Asn Thr Phe Gln Asp Gln Ser Asn Ser 805 810 815 Phe Lys Arg Asp Ala Ala Leu Thr Thr Leu Gly Gln Leu Ala Ala Ser 820 825 830 Ser Gly Tyr Val Val Gly Pro Leu Leu Asp Tyr Pro Glu Leu Leu Gly 835 840 845 Ile Leu Ile Asn Ile Leu Lys Thr Glu Asn Asn Pro His Ile Arg Arg 850 855 860 Gly Thr Val Arg Leu Ile Gly Ile Leu Gly Ala Leu Asp Pro Tyr Lys 865 870 875 880 His Arg Glu Ile Glu Val Thr Ser Asn Ser Lys Ser Ser Val Glu Gln 885 890 895 Asn Ala Pro Ser Ile Asp Ile Ala Leu Leu Met Gln Gly Val Ser Pro 900 905 910 Ser Asn Asp Glu Tyr Tyr Pro Thr Val Val Ile His Asn Leu Met Lys 915 920 925 Ile Leu Asn Asp Pro Ser Leu Ser Ile His His Thr Ala Ala Ile Gln 930 935 940 Ala Ile Met His Ile Phe Gln Asn Leu Gly Leu Arg Cys Val Ser Phe 945 950 955 960 Leu Asp Gln Ile Ile Pro Gly Ile Ile Leu Val Met Arg Ser Cys Pro 965 970 975 Pro Ser Gln Leu Asp Phe Tyr Phe Gln Gln Leu Gly Ser Leu Ile Ser 980 985 990 Ile Val Lys Gln His Ile Arg Pro His Val Glu Lys Ile Tyr Gly Val 995 1000 1005 Ile Arg Glu Phe Phe Pro Ile Ile Lys Leu Gln Ile Thr Ile Ile Ser 1010 1015 1020 Val Ile Glu Ser Ile Ser Lys Ala Leu Glu Gly Glu Phe Lys Arg Phe 1025 1030 1035 1040 Val Pro Glu Thr Leu Thr Phe Phe Leu Asp Ile Leu Glu Asn Asp Gln 1045 1050 1055 Ser Asn Lys Arg Ile Val Pro Ile Arg Ile Leu Lys Ser Leu Val Thr 1060 1065 1070 Phe Gly Pro Asn Leu Glu Asp Tyr Ser His Leu Ile Met Pro Ile Val 1075 1080 1085 Val Arg Met Thr Glu Tyr Ser Ala Gly Ser Leu Lys Lys Ile Ser Ile 1090 1095 1100 Ile Thr Leu Gly Arg Leu Ala Lys Asn Ile Asn Leu Ser Glu Met Ser 1105 1110 1115 1120 Ser Arg Ile Val Gln Ala Leu Val Arg Ile Leu Asn Asn Gly Asp Arg 1125 1130 1135 Glu Leu Thr Lys Ala Thr Met Asn Thr Leu Ser Leu Leu Leu Leu Gln 1140 1145 1150 Leu Gly Thr Asp Phe Val Val Phe Val Pro Val Ile Asn Lys Ala Leu 1155 1160 1165 Leu Arg Asn Arg Ile Gln His Ser Val Tyr Asp Gln Leu Val Asn Lys 1170 1175 1180 Leu Leu Asn Asn Glu Cys Leu Pro Thr Asn Ile Ile Phe Asp Lys Glu 1185 1190 1195 1200 Asn Glu Val Pro Glu Arg Lys Asn Tyr Glu Asp Glu Met Gln Val Thr 1205 1210 1215 Lys Leu Pro Val Asn Gln Asn Ile Leu Lys Asn Ala Trp Tyr Cys Ser 1220 1225 1230 Gln Gln Lys Thr Lys Glu Asp Trp Gln Glu Trp Ile Arg Arg Leu Ser 1235 1240 1245 Ile Gln Leu Leu Lys Glu Ser Pro Ser Ala Cys Leu Arg Ser Cys Ser 1250 1255 1260 Ser Leu Val Ser Val Tyr Tyr Pro Leu Ala Arg Glu Leu Phe Asn Ala 1265 1270 1275 1280 Ser Phe Ser Ser Cys Trp Val Glu Leu Gln Thr Ser Tyr Gln Glu Asp 1285 1290 1295 Leu Ile Gln Ala Leu Cys Lys Ala Leu Ser Ser Ser Glu Asn Pro Pro 1300 1305 1310 Glu Ile Tyr Gln Met Leu Leu Asn Leu Val Glu Phe Met Glu His Asp 1315 1320 1325 Asp Lys Pro Leu Pro Ile Pro Ile His Thr Leu Gly Lys Tyr Ala Gln 1330 1335 1340 Lys Cys His Ala Phe Ala Lys Ala Leu His Tyr Lys Glu Val Glu Phe 1345 1350 1355 1360 Leu Glu Glu Pro Lys Asn Ser Thr Ile Glu Ala Leu Ile Ser Ile Asn 1365 1370 1375 Asn Gln Leu His Gln Thr Asp Ser Ala Ile Gly Ile Leu Lys His Ala 1380 1385 1390 Gln Gln His Asn Glu Leu Gln Leu Lys Glu Thr Trp Tyr Glu Lys Leu 1395 1400 1405 Gln Arg Trp Glu Asp Ala Leu Ala Ala Tyr Asn Glu Lys Glu Ala Ala 1410 1415 1420 Gly Glu Asp Ser Val Glu Val Met Met Gly Lys Leu Arg Ser Leu Tyr 1425 1430 1435 1440 Ala Leu Gly Glu Trp Glu Glu Leu Ser Lys Leu Ala Ser Glu Lys Trp 1445 1450 1455 Gly Thr Ala Lys Pro Glu Val Lys Lys Ala Met Ala Pro Leu Ala Ala 1460 1465 1470 Gly Ala Ala Trp Gly Leu Glu Gln Trp Asp Glu Ile Ala Gln Tyr Thr 1475 1480 1485 Ser Val Met Lys Ser Gln Ser Pro Asp Lys Glu Phe Tyr Asp Ala Ile 1490 1495 1500 Leu Cys Leu His Arg Asn Asn Phe Lys Lys Ala Glu Val His Ile Phe 1505 1510 1515 1520 Asn Ala Arg Asp Leu Leu Val Thr Glu Leu Ser Ala Leu Val Asn Glu 1525 1530 1535 Ser Tyr Asn Arg Ala Tyr Asn Val Val Val Arg Ala Gln Ile Ile Ala 1540 1545 1550 Glu Leu Glu Glu Ile Ile Lys Tyr Lys Lys Leu Pro Gln Asn Ser Asp 1555 1560 1565 Lys Arg Leu Thr Met Arg Glu Thr Trp Asn Thr Arg Leu Leu Gly Cys 1570 1575 1580 Gln Lys Asn Ile Asp Val Trp Gln Arg Ile Leu Arg Val Arg Ser Leu 1585 1590 1595 1600 Val Ile Lys Pro Lys Glu Asp Ala Gln Val Arg Ile Lys Phe Ala Asn 1605 1610 1615 Leu Cys Arg Lys Ser Gly Arg Met Ala Leu Ala Lys Lys Val Leu Asn 1620 1625 1630 Thr Leu Leu Glu Glu Thr Asp Asp Pro Asp His Pro Asn Thr Ala Lys 1635 1640 1645 Ala Ser Pro Pro Val Val Tyr Ala Gln Leu Lys Tyr Leu Trp Ala Thr 1650 1655 1660 Gly Leu Gln Asp Glu Ala Leu Lys Gln Leu Ile Asn Phe Thr Ser Arg 1665 1670 1675 1680 Met Ala His Asp Leu Gly Leu Asp Pro Asn Asn Met Ile Ala Gln Ser 1685 1690 1695 Val Pro Gln Gln Ser Lys Arg Val Pro Arg His Val Glu Asp Tyr Thr 1700 1705 1710 Lys Leu Leu Ala Arg Cys Phe Leu Lys Gln Gly Glu Trp Arg Val Cys 1715 1720 1725 Leu Gln Pro Lys Trp Arg Leu Ser Asn Pro Asp Ser Ile Leu Gly Ser 1730 1735 1740 Tyr Leu Leu Ala Thr His Phe Asp Asn Thr Trp Tyr Lys Ala Trp His 1745 1750 1755 1760 Asn Trp Ala Leu Ala Asn Phe Glu Val Ile Ser Met Leu Thr Ser Val 1765 1770 1775 Ser Lys Lys Lys Gln Glu Gly Ser Asp Ala Ser Ser Val Thr Asp Ile 1780 1785 1790 Asn Glu Phe Asp Asn Gly Met Ile Gly Val Asn Thr Phe Asp Ala Lys 1795 1800 1805 Glu Val His Tyr Ser Ser Asn Leu Ile His Arg His Val Ile Pro Ala 1810 1815 1820 Ile Lys Gly Phe Phe His Ser Ile Ser Leu Ser Glu Ser Ser Ser Leu 1825 1830 1835 1840 Gln Asp Ala Leu Arg Leu Leu Thr Leu Trp Phe Thr Phe Gly Gly Ile 1845 1850 1855 Pro Glu Ala Thr Gln Ala Met His Glu Gly Phe Asn Leu Ile Gln Ile 1860 1865 1870 Gly Thr Trp Leu Glu Val Leu Pro Gln Leu Ile Ser Arg Ile His Gln 1875 1880 1885 Pro Asn Gln Ile Val Ser Arg Ser Leu Leu Ser Leu Leu Ser Asp Leu 1890 1895 1900 Gly Lys Ala His Pro Gln Ala Leu Val Tyr Pro Leu Met Val Ala Ile 1905 1910 1915 1920 Lys Ser Glu Ser Leu Ser Arg Gln Lys Ala Ala Leu Ser Ile Ile Glu 1925 1930 1935 Lys Met Arg Ile His Ser Pro Val Leu Val Asp Gln Ala Glu Leu Val 1940 1945 1950 Ser His Glu Leu Ile Arg Met Ala Val Leu Trp His Glu Gln Trp Tyr 1955 1960 1965 Glu Gly Leu Asp Asp Ala Ser Arg Gln Phe Phe Gly Glu His Asn Thr 1970 1975 1980 Glu Lys Met Phe Ala Ala Leu Glu Pro Leu Tyr Glu Met Leu Lys Arg 1985 1990 1995 2000 Gly Pro Glu Thr Leu Arg Glu Ile Ser Phe Gln Asn Ser Phe Gly Arg 2005 2010 2015 Asp Leu Asn Asp Ala Tyr Glu Trp Leu Met Asn Tyr Lys Lys Ser Lys 2020 2025 2030 Asp Val Ser Asn Leu Asn Gln Ala Trp Asp Ile Tyr Tyr Asn Val Phe 2035 2040 2045 Arg Lys Ile Gly Lys Gln Leu Pro Gln Leu Gln Thr Leu Glu Leu Gln 2050 2055 2060 His Val Ser Pro Lys Leu Leu Ser Ala His Asp Leu Glu Leu Ala Val 2065 2070 2075 2080 Pro Gly Thr Arg Ala Ser Gly Gly Lys Pro Ile Val Lys Ile Ser Lys 2085 2090 2095 Phe Glu Pro Val Phe Ser Val Ile Ser Ser Lys Gln Arg Pro Arg Lys 2100 2105 2110 Phe Cys Ile Lys Gly Ser Asp Gly Lys Asp Tyr Lys Tyr Val Leu Lys 2115 2120 2125 Gly His Glu Asp Ile Arg Gln Asp Ser Leu Val Met Gln Leu Phe Gly 2130 2135 2140 Leu Val Asn Thr Leu Leu Gln Asn Asp Ala Glu Cys Phe Arg Arg His 2145 2150 2155 2160 Leu Asp Ile Gln Gln Tyr Pro Ala Ile Pro Leu Ser Pro Lys Ser Gly 2165 2170 2175 Leu Leu Gly Trp Val Pro Asn Ser Asp Thr Phe His Val Leu Ile Arg 2180 2185 2190 Glu His Arg Glu Ala Lys Lys Ile Pro Leu Asn Ile Glu His Trp Val 2195 2200 2205 Met Leu Gln Met Ala Pro Asp Tyr Asp Asn Leu Thr Leu Leu Gln Lys 2210 2215 2220 Val Glu Val Phe Thr Tyr Ala Leu Asn Asn Thr Glu Gly Gln Asp Leu 2225 2230 2235 2240 Tyr Lys Val Leu Trp Leu Lys Ser Arg Ser Ser Glu Thr Trp Leu Glu 2245 2250 2255 Arg Arg Thr Thr Tyr Thr Arg Ser Leu Ala Val Met Ser Met Thr Gly 2260 2265 2270 Tyr Ile Leu Gly Leu Gly Asp Arg His Pro Ser Asn Leu Met Leu Asp 2275 2280 2285 Arg Ile Thr Gly Lys Val Ile His Ile Asp Phe Gly Asp Cys Phe Glu 2290 2295 2300 Ala Ala Ile Leu Arg Glu Lys Phe Pro Glu Lys Val Pro Phe Arg Leu 2305 2310 2315 2320 Thr Arg Met Leu Thr Tyr Ala Met Glu Val Ser Gly Ile Glu Gly Ser 2325 2330 2335 Phe Arg Ile Thr Cys Glu Asn Val Met Lys Val Leu Arg Asp Asn Lys 2340 2345 2350 Gly Ser Leu Met Ala Ile Leu Glu Ala Phe Ala Phe Asp Pro Leu Ile 2355 2360 2365 Asn Trp Gly Phe Asp Leu Pro Thr Lys Lys Ile Glu Glu Glu Thr Gly 2370 2375 2380 Ile Gln Leu Pro Val Met Asn Ala Asn Glu Leu Leu Ser Asn Gly Ala 2385 2390 2395 2400 Ile Thr Glu Glu Glu Val Gln Arg Val Glu Asn Glu His Lys Asn Ala 2405 2410 2415 Ile Arg Asn Ala Arg Ala Met Leu Val Leu Lys Arg Ile Thr Asp Lys 2420 2425 2430 Leu Thr Gly Asn Asp Ile Arg Arg Phe Asn Asp Leu Asp Val Pro Glu 2435 2440 2445 Gln Val Asp Lys Leu Ile Gln Gln Ala Thr Ser Val Glu Asn Leu Cys 2450 2455 2460 Gln His Tyr Ile Gly Trp Cys Pro Phe Trp 2465 2470 64 base pairs nucleic acid single linear cDNA 4 CCGGATCCCG TCGAGCTTCA GTTGAACTAC GGCGTGCTTC TGTAGCCATG GGAGTGCAGG 60 TGGA 64 28 base pairs nucleic acid single linear cDNA 5 GGCCGGAATT CTCATTCCAG TTTTAGAA 28 7 amino acids amino acid linear DNA (genomic) 6 Thr Tyr Asp Pro Asn Gln Pro 1 5 6 amino acids amino acid linear peptide 7 His Ile Asp Phe Gly Asp 1 5 6 amino acids amino acid linear peptide 8 Asn Asp Gln Val Phe Glu 1 5 18 base pairs nucleic acid single linear cDNA 9 GAGCCACCAC GATTTGCT 18 64 base pairs nucleic acid single linear cDNA 10 CCGGATCCCG TCGAGCTTCA GTTGAACTAC GGCGTGCTTC TGTAGCCATG GCGGCGGCCG 60 TTCC 64 28 base pairs nucleic acid single linear cDNA 11 GGCCGGAATT CTCAATCAAT ATCCACTA 28 28 base pairs nucleic acid single linear cDNA NO 12 GGGGGATCCA CNTAYGAYCC NAAYCARC 28 27 base pairs nucleic acid single linear cDNA 13 GCGGAATTCR TCNCCRAART CDATRTG 27 26 base pairs nucleic acid single linear cDNA 14 GGGGGATCCA AYGAYCARGT NTTYGA 26 

What is claimed is:
 1. A rat RAFT1 protein prepared by the process of: (a) contacting a preparation of rat proteins with FKBP12 in the presence of 1 to 10 nM rapamycin; (b) isolating rat proteins which bind to FKBP12 in the presence of 1 to 10 nM rapamycin from those rat proteins which do not bind in the presence of 1 to 10 nM rapamycin; (c) dissociating bound rat proteins from FKBP12 to provide a rat RAFT1 protein.
 2. An isolated and purified RAFT1 protein having the amino acid sequence as shown in SEQ ID NO:1, wherein the acronym RAFT connotes a rapamycin and FKBP12 target. 